Voltage dividing capacitor circuits, supply modulators and wireless communication devices

ABSTRACT

A voltage dividing capacitor circuit includes a first capacitor voltage divider and a second capacitor voltage divider. The first capacitor voltage divider is connected to a second voltage node, the first capacitor voltage divider includes a first flying capacitor and a plurality of first switches, the second voltage node coupled to a second load capacitor, the plurality of first switches connected in series between a first voltage node and a ground node, the first voltage node coupled to a first load capacitor, and the ground node coupled to a ground voltage. The second capacitor voltage divider is connected between the first voltage node and the second voltage node, and includes a second flying capacitor and a plurality of second switches, the plurality of second switches connected in series between the first voltage node and the second voltage node.

CROSS-REFERENCE TO RELATED APPLICATIONS

This US non-provisional application claims the benefit of priority under35 USC § 119 to Korean Patent Application No. 10-2020-0114323, filed onSep. 8, 2020 and to Korean Patent Application No. 10-2021-0005733, filedon Jan. 15, 2021, in the Korean Intellectual Property Office, thedisclosures of each of which are incorporated by reference in theirentirety herein.

BACKGROUND

Various example embodiments generally relate to voltage converters inintegrated circuits, and more particularly to voltage dividing capacitorcircuits, supply modulators, and/or wireless communication devicesincluding the same, and/or methods of operating the same.

Wireless communication devices, such as smartphones, tablets, andInternet of Things (IoT) devices, etc., use WCDMA (3G), LTE, LTEAdvanced (4G), 5G New Radio (NR), etc., technology for high speedcommunication. As communication technology has been increasinglyadvancing, transmission and/or reception signals having a higherpeak-to-average power ratio (PAPR) and a greater bandwidth are desiredand/or required. Thus, if a power supply of a power amplifier of atransmission end is connected to a battery, the efficiency of the poweramplifier decreases. In order to increase the efficiency of a poweramplifier having a high PAPR and a large bandwidth, average powertracking (APT) and/or envelope tracking (ET) is used. When using the ETtechnique, the efficiency and linearity of a power amplifier may beenhanced. A chip that supports the APT technique and/or ET technique isreferred to as a supply modulator.

SUMMARY

Some example embodiments may provide a voltage dividing capacitorcircuit capable of enhancing efficiency of a circuit.

Some example embodiments may provide a supply modulator capable ofperforming discrete ET and providing enhanced electrical efficiency.

Some example embodiments may provide a wireless communication deviceincluding a supply modulator capable of performing discrete ET andenhancing the electrical efficiency of the wireless communicationdevice.

According to some example embodiments, a voltage dividing capacitorcircuit includes a first capacitor voltage divider and a secondcapacitor voltage divider. The first capacitor voltage divider includesconnected to a second voltage node, the first capacitor voltage dividerincluding a first flying capacitor and a plurality of first switches,the second voltage node coupled to a second load capacitor, theplurality of first switches connected in series between a first voltagenode and a ground node, the first voltage node coupled to a first loadcapacitor, and the ground node coupled to a ground voltage. The secondcapacitor voltage divider is connected between the first voltage nodeand the second voltage node, the second capacitor voltage dividerincluding a second flying capacitor and a plurality of second switches,and the plurality of second switches connected in series between thefirst voltage node and the second voltage node.

According to some example embodiments, a voltage dividing capacitorcircuit includes a first capacitor voltage divider including a firstflying capacitor and a plurality of first switches, the plurality offirst switches connected in series between a first voltage node and athird voltage node, the first voltage node coupled to a first loadcapacitor, the third voltage node coupled to a third load capacitor, andthe first capacitor voltage divider connected to a second voltage nodecoupled to a second load capacitor, a second capacitor voltage dividerconnected between the first voltage node and the second voltage node, athird capacitor voltage divider connected between the second voltagenode and the third voltage node, a fourth capacitor voltage dividerconnected between the third voltage node and a ground node coupled to aground voltage, and a fifth capacitor voltage divider connected betweenthe second voltage node and the ground node.

According to some example embodiments, a voltage dividing capacitorcircuit includes a first capacitor voltage divider including a firstflying capacitor and a plurality of first switches, the plurality offirst switches connected in series between a first node and a secondnode, and the first capacitor voltage divider connected to a third node,and a second capacitor voltage divider including a second first flyingcapacitor and a plurality of second switches, the plurality of secondswitches connected in series between the third node and the second node.

According to some example embodiments, a supply modulator includes aDC-DC converter including an inductor connected to a battery voltage,first through third power switches connected between the inductor andone of a first voltage node, a second voltage node and a ground node,respectively, the ground node coupled to a ground voltage, a first loadcapacitor, the first load capacitor connected between the first voltagenode and the ground node, a second load capacitor, the second loadcapacitor connected between the second voltage node and the ground node,and a voltage dividing capacitor circuit including at least twocapacitor voltage dividers, the at least two capacitor voltage dividersconnected to the first voltage node, the second voltage node and theground node, wherein the DC-DC converter is configured to generate acurrent based on an energy stored in the inductor, and output thecurrent to at least one of the first voltage node and the second voltagenode based on a first set of switch control signals, and the voltagedividing capacitor circuit is configured to generate a plurality ofvoltages having different levels based on the current, and output theplurality of voltages to the first voltage node, the second voltage nodeand a first and second intermediate voltage nodes, the firstintermediate voltage node connected between the first voltage node andthe second voltage node, and the second intermediate voltage nodeconnected between the second voltage node and the ground node.

According to at least one example embodiment, a wireless communicationdevice includes a power amplifier configured to generate a radiofrequency (RF) output signal based on a RF input signal, a supplymodulator configured to generate a plurality of voltages in response toan envelope signal of the RF output signal, each of the plurality ofvoltages having different voltage levels, a switch array configured toselect a selected supply voltage from a plurality of voltages based on areceived plurality of switch control signals corresponding to theenvelope signal, and connect the selected supply voltage to the poweramplifier, and a modem configured to extract an envelope of a basebandsignal, and generate the envelope signal based on the extractedenvelope, wherein the supply modulator includes, a DC-DC converterincluding an inductor connected to a battery voltage, first throughthird power switches connected between the inductor and one of a firstvoltage node, a second voltage node, and a ground node, respectively,the ground node coupled to a ground voltage, a first load capacitor, thefirst load capacitor connected between the first voltage node and theground node, a second load capacitor, the second load capacitorconnected between the second voltage node and the ground node, and avoltage dividing capacitor circuit including at least two capacitorvoltage dividers, the at least two capacitor voltage dividers connectedto the first voltage node, the second voltage node, and the ground node,wherein the DC-DC converter is configured to, generate a current basedon an energy stored in the inductor, and output the current to at leastone of the first voltage node and the second voltage node based on powerswitch control signals, and wherein the voltage dividing capacitorcircuit is configured to generate the plurality of voltages havingdifferent voltage levels based on the current, and output the pluralityof voltages to the first voltage node, the second voltage node, and atleast a first and second intermediate voltage nodes, the firstintermediate voltage node connected between the first voltage node andthe second voltage node, and the second intermediate voltage nodeconnected between the second voltage node and the ground node.

According to at least one example embodiment, a wireless communicationdevice includes a first power amplifier configured to generate a firstradio frequency (RF) output signal based on a first RF input signal, asecond power amplifier configured to generate a second RF output signalbased on a second RF input signal, a supply modulator configured tooutput a plurality of voltages having different voltage levels inresponse to receiving a first envelope signal of the first RF outputsignal and a second envelope signal of the second RF output signal, andthe supply modulator is configured to output a first average powervoltage and a second average power voltage based on an average powersignal, a first switch array configured to select a first selectedsupply voltage from the plurality of voltages in response to a pluralityof first switch control signals corresponding to the first envelopesignal, and output the first selected supply voltage to the first poweramplifier, a second switch array configured to select a second selectedsupply voltage from the plurality of voltages in response to a pluralityof second switch control signals corresponding to the second envelopesignal, and output the second selected supply voltage to the secondpower amplifier, a third switch configured to selectively provide thefirst average power voltage to the first power amplifier based on athird switch control signal, and a fourth switch configured toselectively provide the second average power voltage to the second poweramplifier based on a fourth switch control signal, and wherein thesupply modulator includes, a DC-DC converter including an inductorconnected to a battery voltage, first through third power switchesconnected between the inductor and one of a first voltage node, a secondvoltage node, and a ground node coupled to a ground voltage,respectively, a first load capacitor, the first load capacitor connectedbetween the first voltage node and the ground node, and a second loadcapacitor, the second load capacitor connected between the secondvoltage node and the ground node, and a voltage dividing capacitorcircuit including at least two capacitor voltage dividers connected tothe first voltage node, the second voltage node, and the ground node,the DC-DC converter is configured to generate a current based on anenergy stored in the inductor, and provide the current to at least oneof the first voltage node and the second voltage node based on powerswitch control signals, and the voltage dividing capacitor circuit isconfigured to generate the plurality of voltages having differentvoltage levels based on the current, and output the plurality ofvoltages to the first voltage node, the second voltage node, and atleast a first and second intermediate voltage nodes, the firstintermediate voltage node connected between the first voltage node andthe second voltage node, and the second intermediate voltage nodeconnected between the second voltage node and the ground node.

Accordingly, the voltage dividing capacitor circuit includes a pluralityof capacitor voltage dividers connected to a first voltage node, asecond voltage node and a ground node, and each of the capacitor voltagedividers performs voltage conversion in response to phase control signalset. The DC-DC converter provides current at least one of the first andsecond voltage nodes based on battery voltage and the capacitor voltagedividers provide output voltages to load capacitors using voltage basedon the current. Therefore, the SIMO converter may rapidly provide acurrent to a target voltage node to obtain quick response characteristicand since each of the voltage nodes is coupled to the ground voltage viaa corresponding load capacitor, the SIMO converter may reduce outputripple.

BRIEF DESCRIPTION OF THE DRAWINGS

Illustrative, non-limiting example embodiments will be more clearlyunderstood from the following detailed description in conjunction withthe accompanying drawings.

FIG. 1 is a block diagram illustrating a wireless communication deviceaccording to some example embodiments.

FIG. 2A illustrates an example of the digital transmission signalprocessing circuit (DTSPC) in FIG. 1 according to at least one exampleembodiment.

FIG. 2B is a graph for explaining an operation of a supply modulator inFIG. 1 according to at least one example embodiment.

FIG. 3A is a block diagram illustrating an example of a supply modulatoraccording to some example embodiments.

FIG. 3B illustrates an ET reference signal and an average power signalprovided to the main controller in FIG. 3A according to at least oneexample embodiment.

FIG. 4 is a block diagram illustrating an example of the SIMO converterin the supply modulator in FIG. 3A according to some exampleembodiments.

FIG. 5 is a block diagram illustrating an example of the SIMO converterof FIG. 4 according to some example embodiments.

FIG. 6A illustrates a configuration of the first capacitor divider inthe voltage dividing capacitor circuit in FIG. 5 according to someexample embodiments.

FIGS. 6B and 6C illustrate operation of the first capacitor divider inFIG. 6A, respectively according to some example embodiments.

FIG. 7A is a circuit diagram illustrating an example of the voltagedividing capacitor circuit in the SIMO converter of FIG. 5 according tosome example embodiments.

FIG. 7B is a timing diagram illustrating operation of the SIMO converterof FIG. 7A according to at least one example embodiment.

FIG. 7C illustrates operating frequencies of the first through thirdcapacitor dividers based on currents provided to loads from the voltagesnodes in the SIMO converter in FIG. 7A according to at least one exampleembodiment.

FIG. 8A is a circuit diagram illustrating an example of the voltagedividing capacitor circuit in the SIMO converter of FIG. 5 according tosome example embodiments.

FIGS. 8B and 8C illustrate operations of the second capacitor dividerand the fourth capacitor divider in the voltage dividing circuit in FIG.8A, respectively according to some example embodiments.

FIG. 9 is a block diagram illustrating an example of the SIMO converterof FIG. 4 according to some example embodiments.

FIG. 10 is a block diagram illustrating an example of the SIMO converterof FIG. 4 according to some example embodiments.

FIG. 11 is a circuit diagram illustrating an example of the voltagedividing capacitor circuit in the SIMO converter of FIG. 10 according tosome example embodiments.

FIG. 12 is a circuit diagram illustrating an example of the voltagedividing capacitor circuit in the SIMO converter of FIG. 10 according tosome example embodiments.

FIG. 13 is a block diagram illustrating an example of a supply modulatoraccording to some example embodiments.

FIG. 14 is a block diagram illustrating an example of the SIMO converterin the supply modulator in FIG. 13 according to some exampleembodiments.

FIG. 15 illustrates that the SIMO converter in FIG. 14 drives two poweramplifiers in ET-ET mode according to at least one example embodiment.

FIG. 16 illustrates that the SIMO converter in FIG. 14 drives two poweramplifiers in APT-APT mode according to at least one example embodiment.

FIG. 17A illustrates that the SIMO converter in FIG. 14 drives two poweramplifiers in ET-APT mode according to at least one example embodiment.

FIG. 17B illustrates waveforms of the output voltage according to atracking mode in the SIMO converter in FIG. 14 according to at least oneexample embodiment.

FIG. 18 is a circuit diagram illustrating a converter that employs twoDC-DC converters according to some example embodiments.

FIG. 19 is a circuit diagram illustrating a converter that employs twoDC-DC converters according to some example embodiments.

FIG. 20 is a circuit diagram illustrating an example of a voltagedividing capacitor circuit according to some example embodiments.

FIG. 21 is a circuit diagram illustrating an example of a voltagedividing capacitor circuit according to some example embodiments.

FIG. 22 is a circuit diagram illustrating an example of a voltagedividing capacitor circuit according to some example embodiments.

FIG. 23 is a circuit diagram illustrating an example of a voltagedividing capacitor circuit according to some example embodiments.

DETAILED DESCRIPTION

Various example embodiments will be described more fully hereinafterwith reference to the accompanying drawings, in which some exampleembodiments are shown.

FIG. 1 is a block diagram illustrating a wireless communication deviceaccording to some example embodiments.

Referring to FIG. 1 , a wireless communication device 10 may include amodem 40, a supply modulator (SM) 100, a radio frequency integratedcircuit (RFIC) 60, a power amplifier (PA) 90, and/or an antenna ANT, butthe example embodiments are not limited thereto, and for example, thewireless communication device 10 may include a greater or lesser numberof constituent components.

The modem 40 may include a digital transmission signal processingcircuit (DTSPC) 50, a digital reception signal processing circuit(DRSPC) 40, a digital-to-analog converter (DAC) 44, an analog-to-digitalconverter (ADC) 45, and/or a mobile industry processor interface (MIPI)43, but is not limited thereto.

The modem 40 may process a baseband signal BB_T including information tobe transmitted, the information including an in-phase (I) signal and/ora quadrature phase (Q) signal, etc., based on a desired and/orpredetermined communication protocol using the DTSPC 50, but is notlimited thereto. The modem 40 may process a received baseband signalBB_R based on a desired and/or predetermined communication protocolusing the DRSPC 41, but is not limited thereto. For example, the modem40 may process a signal to be transmitted according to a communicationscheme, such as orthogonal frequency division multiplexing (OFDM),orthogonal frequency division multiple access (OFDMA), wideband codemultiple access (WCDMA), and/or high speed packet access+ (HSPA+), etc.,but is not limited thereto. In addition, the modem 400 may process thebaseband signal BB_T and/or BB_R according to and/or based on varioustypes of communication schemes, e.g., radio access technologies (RATs),to which a technique of modulating the amplitude and frequency of atransmission signal is applied.

The modem 40 may extract at least one envelope of the baseband signalBB_T using the DTSPC 50, and may generate at least one envelope signalENV based on the extracted envelope. The modem 40 may generate anaverage power tracking (APT) signal APT_REF based on APT table stored ina memory (not illustrated), may generate an envelope tracking (ET)reference signal ET_REF based on the envelope signal ENV, and/or mayprovide the APT signal APT_REF and the ET reference signal ET_REF to thesupply modulator 100 through the MIPI 43, etc. The extracted envelopemay correspond to an amplitude (e.g., the magnitude of the I signal andQ signal) of the baseband signal BB_T, but the example embodiments arenot limited thereto. The modem 40 may generate a tracking mode signalTMS, etc.

The APT table may store information on desired and/or required powersupply voltage of the power amplifier 90 based on expected (e.g.,anticipated, configured, designed, desired, etc.) power of the antennaANT and may store information on average power signal corresponding tothe desired and/or required power supply voltage. When the expectedpower of the antenna ANT is determined, the modem 40 may generate theaverage power signal based on the APT table and may provide the APTsignal APT_REF to the supply modulator 100, etc.

FIG. 2A illustrates an example of the digital transmission signalprocessing circuit (DTSPC) in FIG. 1 according to at least one exampleembodiment.

Referring to FIG. 2A, the DTSPC 50 may perform various operationsthrough crest factor reduction (CFR) 51, shaping function (SF) 52,digital pre-distortion (DPD) 53, a first delay (DELAY1) 54, and/or asecond delay (DELAY2) 55 in addition to processing the baseband signal,envelope extraction, and/or generation of digital envelope signal, etc.,but the example embodiments are not limited thereto. The DTSPC 50 mayfurther include a plurality of switches 56 and 57, etc., but is notlimited thereto.

The CFR 51 may reduce a PAPR of at least one transmission signal, forexample, the baseband signal BB_T, etc., but not limited thereto. The SF52 may shape the envelope signal ENV such that the efficiency and/orlinearity of the power amplifier 90 is enhanced. The DPD 53 maycompensate for distortion of the power amplifier 90 in a digital region(e.g., a digital domain, etc.). The first delay 54 may adjust a delay ofthe envelope signal ENV and the second delay 56 may adjust a delay ofthe baseband signal BB_T, but the example embodiments are not limitedthereto.

The DTSPC 50 may output the envelope signal ENV and/or the basebandsignal BB_T, etc.

The envelope signal ENV may be directly provided to the supply modulator100 and/or may be provided to the supply modulator 100 via the MIPI 43.The DVC 44 may convert the baseband signal BB_T to a transmission signalTX to be provided to a transmission circuit (TXC) 70, but is not limitedthereto.

Referring back to FIG. 1 , the modem 40 may receive an analog receptionsignal RX from the RFIC 60. The ADC 45 in the modem 40 may convert thereception signal RX to the baseband signal BB_R. The reception signal RXmay be a differential signal, but is not limited thereto.

The RFIC 60 may generate a radio frequency (RF) input signal RF_IN byperforming a frequency up-conversion on the transmission signal TX,and/or may generate a RF output signal RF_OUT by performing a frequencydown-conversion on the reception signal RX. The RFIC 60 may include atransmission circuit 70 to perform the frequency up-conversion, areception circuit 80 to perform the frequency down-conversion, and alocal oscillator LO, etc., but the example embodiments are not limitedthereto. Moreover, one or more of the transmission circuit 70, receptioncircuit, and/or the local oscillator LO may be combined into a singlecircuit, etc.

The transmission circuit 70 may include a first analog baseband filterABF1 71, a first mixer 73 and/or an amplifier (AMP) 75, etc., but is notlimited thereto. The ABF1 71 may include a low pass filter, but is notlimited thereto. The ABF1 71 filters the transmission signal TX andprovides the filtered transmission signal to the first mixer 73. Thefirst mixer 73 may mix a frequency from the local oscillator LO with thefiltered transmission signal and may perform the frequency up-conversionon the transmission signal TX. The transmission signal TX may beprovided to the AMP 75, and the AMP 75 amplifies an output of the firstmixer 73 and provide the RF input signal RF_IN to the power amplifier90, etc.

The power amplifier 90 may receive a supply voltage VCC from the supplymodulator 100, and amplifies the RF input signal RF_IN based on thesupply voltage VCC to generate the RF output signal RF_OUT. The poweramplifier 90 may provide the RF output signal RF_OUT to the duplexer 95,but is not limited thereto.

The reception circuit 80 may include a second analog baseband filterABF2 85, a second mixer 83, and/or a low noise amplifier (LNA) 81, etc.,but the example embodiments are not limited thereto. The ABF2 85 mayinclude a low pass filter, but is not limited thereto.

The LNA 81 may amplify a RF reception signal RF_R received from theduplexer 95 to provide the amplified signal to the second mixer 83, butis not limited thereto. The second mixer 83 may mix a frequency from thelocal oscillator LO with the amplified signal and may perform thefrequency down-conversion on the mixed signal to generate the receptionsignal RX. The ABF2 filters the reception signal RX and provides thefiltered signal to the modem 40.

In some example embodiments, the wireless communication device 10 maytransmit at least one transmission signal through a plurality offrequency bands by using carrier aggregation (CA), but the exampleembodiments are not limited thereto. To this end, the wirelesscommunication device 10 may include a plurality of power amplifiers forpower-amplifying a plurality of RF input signals corresponding to aplurality of carriers, but is not limited thereto. However, one poweramplifier 90 is illustrated in the wireless communication device 10 ofthe Figures for the convenience of explanation, and in one or moreexample embodiments, the wireless communication device 10 may include aplurality of power amplifiers, etc., to support carrier aggregation,etc.

The supply modulator 100 may generate the supply voltage VCC whose levelis dynamically varied (e.g., changed, modified, etc.) based on theenvelope signal ENV and the ET reference signal ET_REF in an ET mode,and may provide the supply voltage VCC to the power amplifier 90. Thesupply modulator 100 may adjust the supply voltage VCC based on theaverage power signal APT_REF in an APT mode and may provide the supplyvoltage VCC to the power amplifier 90.

The supply modulator 100 may generate a plurality of voltages havingdifferent levels, voltage levels, voltage values, etc., based on abattery voltage VBAT (e.g., the battery voltage VBAT may also bereferred to as a power supply voltage, etc.), and may provide one of theplurality of voltages to the power amplifier 90 as the supply voltageVCC based on the envelope signal ENV when in the ET mode (e.g., thewireless communication device 10 and/or the DTSPC 50 is in the ET mode,etc.). The supply modulator 100 may select a voltage corresponding to alevel (e.g., voltage level, voltage value, etc.) of the envelope signalENV and may provide the selected voltage to the power amplifier 90 asthe supply voltage VCC.

When a level (e.g., voltage level, etc.) of the envelope signal ENV issmall (e.g., less than a desired voltage ENV threshold, etc.), thesupply modulator 100 may provide a voltage having a small level (e.g., afirst voltage level, a corresponding voltage level, etc.) to the poweramplifier 90 as the supply voltage VCC. When a level of the envelopesignal ENV is great (e.g., greater than the desired voltage ENVthreshold, etc.), the supply modulator 100 may provide a voltage havinga great level (e.g., a second voltage level, a corresponding voltagelevel, etc.) to the power amplifier 90 as the supply voltage VCC.Therefore, the supply modulator 100 may enhance the efficiency of powerconsumption of the wireless communication device 10 and/or the DTSPC 50and may increase the length of battery use and/or increase the batterycapacity of the wireless communication device 10, etc.

The technique to adjust the level (e.g., voltage level) of the supplyvoltage adaptively based on the envelope signal ENV is referred to asET. The ET according to some example embodiments may be referred to as adiscrete ET because a voltage having a level which is most similar witha level of the envelope signal ENV is selected, but the exampleembodiments are not limited thereto.

The supply modulator 100 may select ET and/or APT based on a selectedtransmission power set in a communication device including the supplymodulator 100, but the example embodiments are not limited thereto.Hereinafter, the example embodiments will be described assuming thesupply modulator 100 performs ET operation for the sake of brevity andclarity, but the example embodiments are not limited thereto, and theoperation of the supply modulator 100 may apply equally to APT operationas well.

The duplexer 95 is coupled to the antenna ANT and may separate atransmission frequency and/or a reception frequency, but the exampleembodiments are not limited thereto. The duplexer 95 may divide the RFoutput signal RF_OUT according to frequency bands and may provide the RFoutput signal RF_OUT to a corresponding antenna ANT. The duplexer 95 mayprovide the LNA 81 in the reception circuit 80 of the RFIC 60 with asignal received from the antenna ANT.

According to some example embodiments, the wireless communication devicemay include at least one switch to separate a transmission frequencyand/or a reception frequency instead of the duplexer 65, but is notlimited thereto. According to other example embodiments, the wirelesscommunication device may include both a switch and a duplexer, etc.

The antenna ANT may transmit the RF output signal RF_OUT whose frequencyis separated to an outside (e.g., may transmit the RF output signalRF_OUT to an external device) and/or may provide the RF reception signalRF_R from the outside (e.g., external source, etc.) to the duplexer 95.The antenna ANT may include an array antenna, etc., but is not limitedthereto.

FIG. 2B is a graph for explaining an operation of a supply modulator inFIG. 1 according to at least one example embodiment.

Referring to FIG. 2B, the supply modulator 100 may modulate the supplyvoltage VCC to be provided to the power amplifier 90, based on theenvelope signal ENV by using DC voltages having different voltagelevels. In other words, the supply modulator 100 may generate the supplyvoltage VCC to have different voltage levels based on the envelopesignal ENV. The supply voltage VCC provided to the power amplifier 90may be referred to as a bias voltage.

FIG. 3A is a block diagram illustrating an example of a supply modulatoraccording to some example embodiments.

Referring to FIG. 3A, a supply modulator 100 a may include a maincontroller 110, a discrete level (DL) controller 120, a switchcontroller 130, a switch array 140 a, and/or a single inductor multipleoutput (SIMO) converter 200, etc., but the example embodiments are notlimited thereto. According to some example embodiments, the supplymodulator 100 a may be implemented as processing circuitry, or in otherwords, processing circuitry included in the supply modulator 100 a maybe capable of performing the functionality of one or more of the supplymodulator 100 a, main controller 110, DL controller 120, switchcontroller 130, switch array 140 a, and/or SIMO converter 200, etc. Theprocessing circuitry may include hardware, such as processors, processorcores, logic circuits, storage devices, etc.; a hardware/softwarecombination such as at least one processor core executing softwareand/or executing any instruction set, etc.; or a combination thereof.For example, the processing circuitry more specifically may include, butis not limited to, a field programmable gate array (FPGA), aprogrammable logic unit, an application-specific integrated circuit(ASIC), a System-on-Chip (SoC), etc.

The main controller 110 may receive the tracking mode signal TMS, theaverage power signal ART_REF, and/or the ET reference signal ET_REF fromthe modem 40 in FIG. 1 , and may determine a tracking mode of the supplymodulator 100 a based on the tracking mode signal TMS, etc., but is notlimited thereto. Additionally, the main controller 110 may generate aplurality of reference voltages VREF1˜VREFn (where n is an integergreater than one) based on the ET reference signal ET_REF in the ETmode, and may provide the plurality of reference voltages VREF1˜VREFn tothe SIMO converter 200, but is not limited thereto. The main controller110 may control the discrete level controller 120, the switch controller130 and/or the SIMO converter 200, etc.

The SIMO converter 200 may generate a plurality of voltages V1˜Vn basedon the battery voltage VBAT under control of and/or based oninstructions from the main controller 110, and may provide the pluralityof voltages V1˜Vn to the switch array 140 a. The SIMO converter 200 maygenerate the plurality of voltages V1˜Vn having different levels (e.g.,voltage levels, voltage values, etc.) based on the plurality ofreference voltages VREF1˜VREFn and the battery voltage VBAT and mayoutput the plurality of voltages V1˜Vn to the switch array 140 a.

The switch array 140 a may include a plurality of switches S1˜Sncorresponding to the plurality of voltages V1˜Vn having different levels(e.g., voltage levels, etc.). The opening and/or closing operation ofthe plurality of switches S1˜Sn may be controlled by and/or based on aswitch control signal SWC provided from the switch controller 130. Theswitch array 140 a may select one or more voltages among the pluralityof voltages V1˜Vn having different levels based on the switch controlsignal SWC, and may provide the selected voltage(s) to the poweramplifier 90, but is not limited thereto.

The discrete level controller 120 may generate a level control signalENV_LV including envelope level information based on the envelope signalENV from the modem 40. The discrete level controller 120 may provide thelevel control signal ENV_LV to the switch controller 130, but is notlimited thereto.

The switch controller 130 may receive the level control signal ENV_LVfrom the discrete level controller 120, and may control on/off (e.g.,the opening and/or closing) of one or more of the plurality of switchesS1˜Sn based on the level control signal ENV_LV. The switch controller130 may generate the switch control signal SWC for controlling on/off ofone or more of the plurality of switches S1˜Sn and may provide theswitch control signal SWC to the switch array 140 a.

In the ET mode, the switch controller 130 may select a voltagecorresponding to a level (e.g. voltage level, etc.) of the envelopesignal ENV among the plurality of voltages V1˜Vn having different levelsand may control the on/off (e.g., control the operation) of theplurality of switches S1˜Sn such that the selected voltage is providedto the power amplifier 90. In addition, in the APT mode, the switchcontroller 130 may control at least one of the plurality of switchesS1˜Sn such that a voltage having a nearest level (e.g., closest voltagelevel) with a desired and/or required level and/or a greater level thanthe desired and/or required level among the plurality of voltages V1˜Vnis selected, but the example embodiments are not limited thereto.

In some example embodiments, the supply modulator 100 a may furtherinclude at least one switch Sa, and the switch Sa may provide the poweramplifier 90 with an APT voltage APT_V provided from the SIMO converter200 based on the average power signal APT_REF in the APT mode. Theswitch controller 130 may turn on the switch Sa in the APT mode, and mayturn off the switch Sa in the ET mode, by applying a switch controlsignal SWCa to the switch Sa, but the example embodiments are notlimited thereto. In the APT mode, the switch controller 130 may turn offthe plurality of switches S1˜Sn.

Although not illustrated, either in the ET mode or in the APT mode, theswitch array 140 a may connect a load capacitor corresponding to thecontrolled switch among load capacitors coupled to a plurality ofvoltage nodes in the SIMO converter 200 to the power amplifier 90. Theload capacitor corresponding to the controlled switch may serve as adecoupling capacitor connected to the supply voltage VCC, but theexample embodiments are not limited thereto.

FIG. 3B illustrates an ET reference signal and an average power signalprovided to the main controller in FIG. 3A according to at least oneexample embodiment.

Referring to FIG. 3B, the ET reference signal ET_REF may include aplurality of reference signals, e.g., ET_VO1, ET_VO2, ET_VO3, and/orET_VO4, etc., corresponding to levels (e.g., voltage levels, etc.) ofthe envelope signal ENV, and the average power signal APT_REF mayinclude average power voltages, e.g., APT_VO1 and/or APT_VO2, etc.

FIG. 4 is a block diagram illustrating an example of the SIMO converterin the supply modulator in FIG. 3A according to some exampleembodiments.

Referring to FIG. 4 , the SIMO converter 200 may include a DC-DCconverter 210 and/or a voltage dividing capacitor circuit 300, etc., butis not limited thereto. The SIMO converter 200 may further include acomparator block 220, a power switch control signal generator (PSCSG)230, and/or a phase control signal generator (PCSG) 235, etc., but isnot limited thereto.

The comparator block 220 may include a plurality of comparators, e.g.,comparators 221, 22, . . . , 22 n that compare each of a plurality ofvoltages, e.g., voltages V1, Va, V2, Vb and Vn, etc., output from thevoltage dividing capacitor circuit 300 with respect to one of theplurality of reference voltages VREF1˜VREFn. The comparator block 220may generate and/or output a plurality of comparison signals, e.g., CS1,CS2, . . . , CSn, etc., based on the results of the comparisons.

The PSCSG 230 may generate a first set of switch control signals SCSbased on a first comparison signal CS1 associated with the first voltageV1 and a second comparison signal CS2 associated with the second voltageV2 among the plurality of comparison signals CS1, CS2, . . . , CSn. ThePSCSG 230 may provide the first set of switch control signal SCS to theDC-DC converter 210.

The PCSG 235 may generate a phase control signal PCS based on theplurality of comparison signals CS1, CS2, . . . , CSn and may providethe phase control signal PCS to the voltage dividing capacitor circuit300.

The DC-DC converter 210 may include an inductor (L) 211 connected to thebattery voltage VBAT to store energy, and the DC-DC converter 210 maytransfer a current based on the battery voltage VBAT to at least one ofa first voltage node VN1 and/or a second voltage node VN2 between thefirst voltage node VN1 and/or a ground node VN connected to a groundvoltage, in response to the first set of power switch control signalSCS.

The voltage dividing circuit 300 may include a plurality of capacitordividers (each of the capacitor dividers may be referred to as acapacitor voltage divider that divides a voltage with a ratio greaterthan one or smaller than one using at least one capacitor), such as,CD1, CD2, CD3, . . . , etc., which are connected between the firstvoltage node VN1, the second voltage node VN2 and the ground node GN.Each of the plurality of capacitor dividers CD1, CD2, CD3, . . . , etc.,may perform one of a voltage boosting operation and a voltage dropoperation, individually, in response to receiving a phase control signalset. The voltage dividing circuit 300 may output the plurality ofvoltages V1, Va, V2, Vb, and Vn, etc., at the first voltage node VN1,the second voltage node VN2 and intermediate voltage nodes IVNa, andIVNb between the first voltage node VN1 and the second voltage node VN2,and between the second voltage node VN2 and the ground node GN, but arenot limited thereto.

The DC-DC converter 210 may include the inductor 211, first throughthird power switches SW1, SW2 and SW3, a first load capacitor CL1 and/ora second load capacitor CL2, but the example embodiments are not limitedthereto.

The inductor 211 is connected between the battery voltage VBAT and afirst switching node SN1, and stores energy when a current based on thebattery voltage VBAT flows through the inductor 211.

The first power switch SW1 may be connected between the first switchingnode SN1 and the first voltage node VN1, and may transfer the energystored in the inductor 211 to the first voltage node VN1 in the form ofcurrent in response to a first switch control signal SCS1. The secondpower switch SW2 may be connected between the first switching node SN1and the second voltage node VN2, and may transfer the energy stored inthe inductor 211 to the second voltage node VN2 in the form of currentin response to a second switch control signal SCS2.

The third power switch SW3 may be connected between the first switchingnode SN1 and the ground node GN, and may couple the first switching nodeSN1 to the ground node GN in response to a third switch control signalSCS3. When a level of the battery voltage VBAT is smaller than or equalto a voltage level of the second voltage node VN2, the third powerswitch SW3 may perform a current build-up operation by coupling thefirst switching node SN1 to the ground voltage.

In some example embodiments, the first power switch SW1 may include ap-channel metal-oxide semiconductor (PMOS) transistor, the second powerswitch SW2 may include an n-channel metal-oxide semiconductor (NMOS)transistor and the third power switch SW3 may include an NMOStransistor, however the example embodiments are not limited thereto.

FIG. 5 is a block diagram illustrating an example of the SIMO converterof FIG. 4 according to some example embodiments.

FIG. 5 illustrates an example in which a SIMO converter 200 a generatesfour output voltages, but is not limited thereto, and may generate agreater or lesser number of output voltages.

Referring to FIG. 5 , the SIMO converter 200 a may include the DC-DCconverter 210, a voltage dividing capacitor circuit 300 a, a comparatorblock 220 a, PSCSG 230 a and/or a PCSG 235 a, etc.

The DC-DC converter 210 may be the same as the DC-DC converter 210 inFIG. 4 , and duplicate description with FIG. 4 will be omitted.

The comparator block 220 a may include a plurality of comparators 221,222, 223 and 224, etc., that compare each of a plurality of voltages V1,V2, V3 and V4, etc., with respective one of a plurality of referencevoltages VREF1, VREF2, VREF3 and VREF4, etc., and the comparator block220 a may generate and/or output a plurality of comparison signals CS11,CS12, CS13 and CS14, etc., based on the results of the comparisons.

The PSCSG 230 a may generate a first set of switch control signals SCSabased on a first comparison signal CS11 and a second comparison signalCS12, and may provide the first set of switch control signals SCSa tothe DC-DC converter 210. The first set of switch control signals SCSamay include switch control signals SCS1, SCS2 and SCS3, but is notlimited thereto.

The PCSG 235 a may generate a phase control signal PCSa based on theplurality of comparison signals CS1, CS2, CS3 and CS4, etc., and mayprovide the phase control signal PCSa to the voltage dividing capacitorcircuit 300 a.

The voltage dividing circuit 300 a may include first through thirdcapacitor dividers 310, 320 and 330, but is not limited thereto.

The first capacitor divider 310 may be connected between a first voltagenode VN1 coupled to a first load capacitor CL1, a second voltage nodeVN2 coupled to a second load capacitor CL2, and the ground node GN, butis not limited thereto. The second capacitor divider 320 may beconnected between the first voltage node VN1, a first intermediatevoltage node IVN1, and the second voltage node VN2, but is not limitedthereto. The third capacitor divider 330 may be connected between thesecond voltage node VN2, a second intermediate voltage node IVN2 and theground node GN, but is not limited thereto. The first intermediatevoltage node IVN1 may be coupled to a third load capacitor CL3 connectedto the ground voltage and the second intermediate voltage node IVN2 maybe coupled to a fourth load capacitor CL4 connected to the groundvoltage, but the example embodiments are not limited thereto.

When the DC-DC converter 210 generates (and/or, provides) a firstvoltage V1 to the first voltage node VN1 coupled to the first loadcapacitor CL1 through the first power switch SW1, the first capacitordivider 310 may provide a second voltage V2 based on the first voltageV1 at the second voltage node VN2. The second voltage V2 may correspondto a desired percentage of the first voltage V1, for example, a half(e.g., one half, 50%, etc.) of the first voltage V1, but is not limitedthereto. When the level of the battery voltage VBAT is smaller than orequal to the second voltage V2, the DC-DC converter 210 may supply thefirst voltage V1 to the first voltage node VN1 through the first powerswitch SW1. The PSCSG 230 a may determine a level (e.g., voltage level)of the battery voltage VBAT based on the first comparison signal CS11and the second comparison signal CS12, etc.

The second voltage divider 320 may provide (and/or output) a thirdvoltage at the first intermediate voltage node IVN1 based on the firstvoltage V1 and the second voltage V2, but is not limited thereto. Thethird voltage V3 may correspond to a desired percentage of a sum of thefirst voltage V1 and second voltage V2, for example, a half of a sum ofthe first voltage V1 and the second voltage V2, but the exampleembodiments are not limited thereto. The third capacitor divider 330 mayprovide (and/or, output) a fourth voltage V4 based on the second voltageV2 to the second intermediate voltage node IVN2. The fourth voltage V4may correspond to a desired percentage of the second voltage V2, forexample, a half of the second voltage V2, but is not limited thereto.

Therefore, the voltage dividing capacitor circuit 300 a may outputvoltages corresponding to, e.g., V1, (3/4)*V1, (2/4)*V1 and (1/4)*V1 atthe first voltage node VN1, the intermediate voltage node IVN1, thesecond node VN2 and the second intermediate voltage node IVN2,respectively, but is not limited thereto. The voltages corresponding toV1, (3/4)*V1, (2/4)*V1 and (1/4)*V1 have different levels (e.g., voltagelevels).

When the DC-DC converter 210 generates (and/or, provides) the secondvoltage V2 to the second voltage node VN2, the first capacitor divider310 may provide the first voltage V1 to the first voltage node VN1 basedon the second voltage V2, etc.

The DC-DC converter 210 may provide a voltage to one or more of thefirst voltage node VN1 and the second voltage node VN2, and the voltagedividing capacitor circuit 300 a may generate a voltage at another nodebased on the voltage which is generated by the DC-DC converter 210 andis provided to at one node.

FIG. 6A illustrates a configuration of the first capacitor divider inthe voltage dividing capacitor circuit in FIG. 5 according to someexample embodiments.

FIGS. 6B and 6C illustrate operation of the first capacitor divider inFIG. 6A, respectively according to some example embodiments.

Referring to FIG. 6A, the first capacitor divider 310 may include aplurality of transistors, e.g., transistors 311, 312, 313 and 314, etc.,connected in series between the first voltage node VN1 and the groundnode GN, and a flying capacitor CF connected between a node N11 and anode N12, etc. According to at least one example embodiment, the flyingcapacitor CF may be connected in parallel to one or more transistors,such as the transistors 312 and/or 313, etc., but the exampleembodiments are not limited thereto. Each of the transistors 311, 312,313 and 314 may be referred to as a switch.

The transistor 311 is connected between the first voltage node VN1 andthe node N11, the transistor 312 is connected between the node N11 andthe second voltage node VN2, the transistor 313 is connected between thesecond voltage node VN2 and the node N12 and the transistor 314 isconnected between the second voltage node VN2 and the ground node GN,etc.

As illustrated in FIG. 6B, when the transistors 311 and 313 are turnedon and the transistors 312 and 314 are turned off in response to firststate of phase control signals Φ1 and Φ1B, the first capacitor divider310 stores, in the flying capacitor CF, a voltage corresponding to adifference between the first voltage V1 and the second voltage V2, butis not limited thereto. In this case, a relationship of a voltage VCFstored in the flying capacitor CF, the first voltage V1 and the secondvoltage V2 may be represented as VCF=V1−V2, but the example embodimentsare not limited thereto.

As illustrated in FIG. 6C, when the transistors 311 and 313 are turnedoff and the transistors 312 and 314 are turned on in response to secondstate of the phase control signals Φ1 and Φ1B, the voltage stored in theflying capacitor CF is provided to the second voltage node VN2 and isstored in the second load capacitor CL2 coupled to the second voltagenode VN2. In this case, a relationship between the voltage VCF and thesecond voltage V2 is represented as VCF=V2. Therefore, a representationof V1−V2=V2 then V2=(1/2)*V1, but the example embodiments are notlimited thereto.

When the DC-DC converter 210 provides the first voltage V1 to the firstvoltage node VN1 through the first power switch SW1, the first capacitordivider 310 performs a voltage drop operation based on the first voltageV1 in response to the phase control signals. The DC-DC converter 210then outputs the second voltage V2 to the second voltage node VN2. Inaddition, when the DC-DC converter 210 provides the second voltage V2 tothe second voltage node VN2 through the second power switch SW2, thefirst capacitor divider 310 performs a voltage boosting operation basedon the second voltage V2 in response to the phase control signals andoutputs the first voltage V1 at the first voltage node VN1.

Therefore, the SIMO converter 200 a may rapidly generate and/or providea current to a target voltage node that desires and/or needs to supply aload current through the plurality of capacitor dividers, e.g.,capacitor dividers 310, 320 and 330, etc., and thus a responsecharacteristic of the SIMO converter 200 a is fast. In addition, theSIMO converter 200 a may increase, maintain and/or prevent efficiencyfrom being reduced, because a number of capacitors from the DC-Dcconverter 200 to the target node is smaller than a number of capacitorsin a SIMO converter in which capacitor dividers are sequentiallyconnected. In addition, since each of the plurality of capacitordividers 310, 320 and 330 may be controlled based on individual phasecontrol signals, the switching loss may be reduced. In addition, sinceeach of the voltage nodes is coupled to the ground voltage via acorresponding load capacitor, effective capacitance increases and theripple characteristic of the SIMO converter 200 a may be enhanced.

FIG. 7A is a circuit diagram illustrating an example of the voltagedividing capacitor circuit in the SIMO converter of FIG. 5 according tosome example embodiments.

In FIG. 7A, the DC-DC converter 210 is illustrated together for theconvenience of explanation, but the example embodiments are not limitedthereto.

Referring to FIG. 7A, the voltage dividing circuit 300 a may include thefirst through third capacitor dividers 310, 320 and 330, but is notlimited thereto.

The first capacitor divider 310 may include a plurality of transistors311, 312, 313 and 314, etc., connected in series between the firstvoltage node VN1 and the ground node GN, and a flying capacitor CFconnected between a node N11 and a node N12. According to some exampleembodiments, the flying capacitor CF may be in parallel to one or moretransistors, e.g., transistors 312 and/or 313, etc., but the exampleembodiments are not limited thereto.

The transistor 311 is connected between the first voltage node VN1 andthe node N11, the transistor 312 is connected between the node N11 andthe second voltage node VN2, the transistor 313 is connected between thesecond voltage node VN2 and the node N12, and the transistor 314 isconnected between the second voltage node VN2 and the ground node GN,but the example embodiments are not limited thereto.

Each gate of the transistors 311 and 313 receives a first phase controlsignal Φ1, and each gate of the transistors 312 and 314 receives a firstinversion phase control signal Φ1B which has a phase difference of 180degrees with respect to the first phase control signal Φ1, but is notlimited thereto. When the transistors 311 and 313 are turned on, and thetransistors a312 and 314 are turned off, the first capacitor divider 310stores, in the flying capacitor CF, a voltage corresponding to adifference between the first voltage V1 and the second voltage V2. Whenthe transistors 311 and 313 are turned off, and the transistors 312 and314 are turned, the voltage stored in the flying capacitor CF isprovided to the second voltage node VN2 and is stored in the second loadcapacitor CL2, but is not limited thereto.

The second capacitor divider 320 may include a plurality of transistors,e.g., 321, 322, 323 and 324, etc., connected in series between the firstvoltage node VN1 and the second voltage node VN2, and a flying capacitorCF connected between a node N21 and a node N22. According to someexample embodiments, the flying capacitor CF may be connected inparallel to one or more transistors, e.g., transistors 322 and/or 323,etc., but the example embodiments are not limited thereto. Each gate ofthe transistors 321 and 323 receives a second phase control signal Φ2,and each gate of the transistors 322 and 324 receives a second inversionphase control signal Φ2B which has a phase difference of 180 degreeswith respect to the second phase control signal Φ2, but the exampleembodiments are not limited thereto.

As described with reference to FIGS. 6B and 6C, the second capacitordivider 320 may provide the third voltage V3 based on the first voltageV1 and the second voltage V2, in response to the second phase controlsignal Φ2 and the second inversion phase control signal Φ2B, etc.

The third capacitor divider 330 may include a plurality of transistors,e.g., 331, 332, 333 and 334, etc., connected in series between thesecond voltage node VN2 and the ground node GN, and a flying capacitorCF connected between a node N31 and a node N32, etc. According to someexample embodiments, the flying capacitor CF may be connected inparallel to one or more transistors, e.g., transistors 332 and/or 333,etc., but the example embodiments are not limited thereto. Each gate ofthe transistors 331 and 333 receives a third phase control signal Φ3,and each gate of the transistors 332 and 334 receives a third inversionphase control signal Φ3B which has a phase difference of 180 degreeswith respect to the third phase control signal Φ3, but the exampleembodiments are not limited thereto.

As described with reference to FIGS. 6B and 6C, the third capacitordivider 330 may provide the fourth voltage V4 based on the secondvoltage V2, in response to the third phase control signal Φ3 and thethird inversion phase control signal Φ3B, but is not limited thereto.

When the DC-DC converter 210 provides current to the first voltage nodeVN1 and the second voltage node VN2, the second capacitor divider 320generates the third voltage V3 based on the first voltage V1 and thesecond voltage V2, and the second capacitor divider 320 provides thethird voltage V3 to the first intermediate voltage node IVN1. Inaddition, while the second capacitor divider 320 generates the thirdvoltage V3, the third capacitor divider 330 generates the fourth voltageV4 based on the second voltage V2, and provides the fourth voltage V4 tothe second intermediate voltage node IVN2. In this case, the currentprovided to the first voltage node VN1 and the second voltage node VN2via the first power switch SW1 and the second power switch SW2 has amagnitude corresponding to, for example, a half of a magnitude ofcurrent provided to either the first voltage node VN1 or the secondvoltage node VN2 through one current path and efficiency of the SIMOconverter 300 a may increase by four times, but the example embodimentsare not limited thereto.

When the DC-DC converter 210 performs a converting operation (e.g.,conversion operation) using the first power switch SW1 and the thirdpower switch SW3, the DC-DC converter 210 may increase a magnitude ofcurrent provided to the first voltage node VN1 by performing a currentbuild-up operation using the inductor 211. In this case, the firstcapacitor divider 310 generates the second voltage V2 based on the firstvoltage V1. In addition, the second capacitor divider 320 generates thethird voltage V3 based on the first voltage V1 and the second voltageV2, and provides the third voltage V3 to the first intermediate voltagenode IVN1. In addition, while the second capacitor divider 320 generatesthe third voltage V3, the third capacitor divider 330 generates thefourth voltage V4 based on the second voltage V2, and provides thefourth voltage V4 to the second intermediate voltage node IVN2.

When the second power switch SW2 and the third power switch SW3 areturned on in the DC-DC converter 210, the DC-DC converter 210 performs acurrent build-up operation using the inductor 211. Additionally, thefirst capacitor divider 310 and the third capacitor divider 330 generatethe first voltage V1 and the third voltage V3 based on the secondvoltage V2, respectively. In this case, the SIMO converter 300 a mayincrease efficiency of the entire circuit by reducing the amount ofcurrent from the battery voltage VBAT.

When the level of the battery voltage VBAT is smaller than the level ofthe second voltage V2 and/or when the battery voltage VBAT is not enough(e.g., the battery voltage VBAT does not meet a desired thresholdvoltage and/or the power demands of the electronic device, etc.), thefirst power switch SW1, the second power switch SW2 and the third powerswitch SW3 may be turned on in the DC-DC converter 210. In this case,the second capacitor divider 320 generates the third voltage V3 based onthe first voltage V1 and the second voltage V2, and provides the thirdvoltage V3 to the first intermediate voltage node IVN1. In addition,while the second capacitor divider 320 generates the third voltage V3,the third capacitor divider 330 generates the fourth voltage V4 based onthe second voltage V2, and provides the fourth voltage V4 to the secondintermediate voltage node IVN2, but the example embodiments are notlimited thereto.

FIG. 7B is a timing diagram illustrating operation of the SIMO converterof FIG. 7A according to at least one example embodiment.

Referring to FIG. 7B, the battery voltage VBAT and the plurality ofreference voltages VREF1, VREF2, VREF3 and VREF4 are illustrated, butthe example embodiments are not limited thereto. FIG. 7B illustrates acase when the DC-DC converter 210 provides current to the first voltagenode VN1 and the second voltage node VN2, and the second capacitordivider 320 and the third capacitor divider 330 generates the thirdvoltage V3 and the fourth voltage V4, respectively, but the exampleembodiments are not limited thereto.

When the reference voltage VREF1 begins to increase at time t1 andreaches a constant level at time t2, each of the first through fourthvoltages V1, V2, V3 and V4 reaches a constant level at time t2 and theconstant level is maintained until time t3. Therefore, the operatingfrequencies of the phase control signals Φ1, Φ2 and Φ3 are constant fromtimes t1 to t3, but the example embodiments are not limited thereto.When the level of the third voltage V3 decreases at time t3 due to aload current provided to a load from the first intermediate voltage nodeIVN1 increasing at time t3, the operating frequencies of the phasecontrol signals Φ1, Φ1B, Φ2 and Φ2B applied to the capacitor divider 310and the second capacitor divider 320 associated with the third voltageV3 increase.

Accordingly, the level of the third voltage V3 increase from time t3 totime t5. The operating frequencies of the phase control signals Φ1, Φ1B,Φ2 and Φ2B applied to the capacitor divider 310 and the second capacitordivider 320 decrease from time t4 to time t5, at which the level of thethird voltage V3 becomes greater than a level of the reference voltageVREF3. Therefore, the level of the third voltage V2 stops increasing attime t6 and converges to the reference voltage VREF3. When a voltage atthe load capacitor varies based on a magnitude of the load current, theSIMO converter 200 a may cope with the change of the voltage byincreasing or decreasing a frequency of a phase control signal appliedto the corresponding capacitor divider. The interval from time t6 totime t7 is similar with the interval from time t4 to time t5, etc.

FIG. 7C illustrates operating frequencies of the first through thirdcapacitor dividers based on currents provided to loads from the voltagesnodes in the SIMO converter in FIG. 7A according to at least one exampleembodiment.

In FIG. 7C, a reference numeral 411 illustrates a magnitude of a currentIo provided to a load from the first voltage node VN1, and associatedoperating frequencies of the phase control signal Φ1 applied to thefirst capacitor divider 310, and the phase control signal Φ2 applied tothe second capacitor divider 320. A reference numeral 412 illustrates amagnitude of a current Io provided to a load from the second voltagenode VN2 and associated operating frequency of the phase control signalΦ1 applied to the first capacitor divider 310. A reference numeral 413illustrates a magnitude of a current Io provided to a load from thefirst intermediate voltage node IVN1 and associated operatingfrequencies of the phase control signal Φ1 applied to the firstcapacitor divider 310 and the phase control signal Φ2 applied to thesecond capacitor divider 320. A reference numeral 414 illustrates amagnitude of a current Io provided to a load from the secondintermediate voltage node IVN2 and associated operating frequencies ofthe phase control signal Φ1 applied to the first capacitor divider 310and the phase control signal Φ3 applied to the third capacitor divider330.

Referring to FIG. 7C, it is noted that the operating frequency of acorresponding capacitor divider increases when a load current increases,the load current consumed by a load connected to each of the firstvoltage node VN1, the second voltage node VN2, the first intermediatevoltage node IVN1 and the second intermediate voltage node IVN2 at whichone of the first through fourth voltages V1, V2, V3 and V4,respectively, is provided.

FIG. 8A is a circuit diagram illustrating an example of the voltagedividing capacitor circuit in the SIMO converter of FIG. 5 according tosome example embodiments.

In FIG. 8A, the DC-DC converter 210 is illustrated together with thevoltage dividing circuit 300 b for the sake of brevity and convenienceof explanation, but the example embodiments are not limited thereto andother DC-DC converter designs may be implemented.

A voltage dividing circuit 300 b in FIG. 8A differs from the voltagedividing circuit 300 a in FIG. 7A in that the voltage dividing circuit300 b further includes at least a fourth capacitor divider 320 b, but isnot limited thereto.

The fourth capacitor divider 320 b may be connected between the firstvoltage node VN1 and the second voltage node VN2 in parallel with thesecond capacitor divider 320, and may include a plurality of transistors321 b, 322 b, 323 b and 324 b, etc., connected in series between thefirst voltage node VN1 and the second voltage node VN2, and a flyingcapacitor CF connected between a node N21 b and a node N22 b. Accordingto some example embodiments, the flying capacitor CF may be connected inparallel to one or more transistors, e.g., transistors 322 b and/or 323b, etc., but the example embodiments are not limited thereto. Each gateof the transistors 321 b and 323 b receives the second inversion phasecontrol signal Φ2B, and each gate of the transistors 322 and 324receives the second phase control signal Φ2.

FIGS. 8B and 8C illustrate operations of the second capacitor dividerand the fourth capacitor divider in the voltage dividing circuit in FIG.8A, respectively, according to some example embodiments.

Referring to FIGS. 8B and 8C, the second capacitor divider 320 and thefourth capacitor divider 320 b may operate complementarily in responseto the second phase control signal Φ2 and the second inversion phasecontrol signal Φ2B, and may provide additional current to the firstintermediate voltage node IVN1 when a current provided to the load fromthe first intermediate voltage node IVN1 increases. When a currentprovided to the load from the first intermediate voltage node IVN1increases, additional current is desired and/or needs to be provided tothe first intermediate voltage node IVN1. When the fourth capacitordivider 320 b supplies the additional current to the first intermediatevoltage node IVN1, each of the second capacitor divider 320 and thefourth capacitor divider 320 b provide a desired percentage, such ashalf of current, to be provided to the intermediate voltage node IVN1and thus transient response becomes fast and power consumption may bereduced.

FIG. 9 is a block diagram illustrating an example of the SIMO converterof FIG. 4 according to some example embodiments.

Referring to FIG. 9 , a SIMO converter 200 b may include a DC-DCconverter 210 b, a voltage dividing capacitor circuit 300 b, acomparator block 220 a, a PSCSG 230 c, and/or a PCSG 235 a, etc., butthe example embodiments are not limited thereto.

The SIMO converter 200 b of FIG. 9 differs from the SIMO converter 200 bof FIG. 9 in the DC-DC converter 210 b and the PSCSG 230 c.

The PSCSG 230 c may generate a first set of switch control signal SCSbbased on a first control signal CTL1 received from the modem 40, thefirst comparison signal CS11, and the second comparison signal CS12received from the comparator block 220 a. The PSCSG 230 c may providethe first set of switch control signal SCSb to the DC-DC converter 210b. The first set of switch control signal SCSb may include switchcontrol signals SCS1, SCS2, SCS3, SCS4 and SCS5, etc., but is notlimited thereto. The first control signal CTL1 may designate anoperation mode of the DC-DC converter 210 b, e.g., the operation modemay be one of a buck mode or a boost mode, etc.

The DC-DC converter 210 b may include an inductor 211, first throughfifth power switches SW1, SW2, SW3, SW4 and SW5, a first load capacitorCL1 and a second load capacitor CL2, but is not limited thereto.

The inductor 211 may be connected between a first switching node SN1 anda second switching node SN2, but is not limited thereto. The first powerswitch SW1 may be connected between the first switching node SN1 and thefirst voltage node VN1. The second power switch SW2 may be connectedbetween the first switching node SN1 and the second voltage node VN2.The third power switch SW3 may be connected between the first switchingnode SN1 and the ground node GN. The fourth power switch SW4 may beconnected between the second switching node SN2 and the battery voltageVBAT, and may have a gate to receive a fourth switch control signalSCS4. The fifth power switch SW5 may be connected between the secondswitching node SN2 and the ground node GN, and may have a gate toreceive a fifth switch control signal SCS5.

In the SIMO converter 200 b of FIG. 9 , the DC-DC converter 210 bfurther includes the fourth power switch SW4 and the power switch SW5,and the DC-DC converter 210 b may operate either in a buck mode in whichthe DC-DC converter 210 b generates a voltage whose level is smallerthan a level of the battery voltage VBAT, or in a boost mode in whichthe DC-DC converter 210 b generates a voltage whose level is greaterthan a level of the battery voltage VBAT.

When a voltage equal to or smaller than the second voltage V2 is to beused, the DC-DC converter 210 b operates in the buck mode by turning onthe second power switch SW2, and a battery current provided to the firstvoltage node VN1 may be reduced because the first capacitor divider 310generates the second voltage V2 based on the first voltage V1. In thiscase, when the first voltage V1 is generated, the second voltage V2 isgenerated based on the first voltage V1, and the second voltage V2 istransferred causing an increase in power loss. However, when the DC-DCconverter 210 b directly generates the second voltage V2 based on thebattery voltage VBAT, the first voltage V1 may be maintained by thefirst capacitor divider 310, and thus the power loss may be reduced.

FIG. 10 is a block diagram illustrating an example of the SIMO converterof FIG. 4 according to some example embodiments.

Referring to FIG. 10 , a SIMO converter 200 c may include a DC-DCconverter 210, a voltage dividing capacitor circuit 300 c, a comparatorblock 220 c, a PSCSG 230 b, and/or a PCSG 235 c, etc., but is notlimited thereto.

The configuration and operation of the DC-DC converter 210 and the PSCSG230 b of FIG. 10 may be the same as the configuration and operation ofthe DC-DC converter 210 and the PSCSG 230 b in FIG. 5 , respectively,but the example embodiments are not limited thereto.

The comparator block 220 c may include a plurality of comparators221-228 that compare each of a plurality of voltages V1˜V4 with arespective reference voltage from a plurality of reference voltagesVREF1˜VREF8, and the comparator block 220 c may generate and/or output aplurality of comparison signals CS21˜CS28. The PCSG 235 c may generate aphase control signal PCSb based on the plurality of comparison signalsCS21˜CS28, and may provide the phase control signal PCSb to the voltagedividing capacitor circuit 300 c.

The voltage dividing circuit 300 c may include first through seventhcapacitor dividers 310˜370, but is not limited thereto.

The first through third capacitor dividers 310, 320 and 330 of FIG. 10may be the same as the first through third capacitor dividers 310, 320and 330 in FIG. 5 , but the example embodiments are not limited thereto.

The fourth capacitor divider 340 may be connected to the first voltagenode VN1, the first intermediate voltage node IVN1, and a thirdintermediate voltage node IVN3, and the fourth capacitor divider 340 maygenerate and output a fifth voltage V5 to the third intermediate voltagenode IVN3. The fifth capacitor divider 350 may be connected to the firstintermediate voltage node IVN1, the second voltage node VN2, and afourth intermediate voltage node IVN4, and the fifth capacitor divider340 may generate and output a sixth voltage V6 to the fourthintermediate voltage node IVN4.

The sixth capacitor divider 360 may be connected to the second voltagenode VN2, the second intermediate voltage node IVN2, and a fifthintermediate voltage node IVN5, and the sixth capacitor divider 360 maygenerate and output a seventh voltage V7 to the fifth intermediatevoltage node IVN5. The seventh capacitor divider 370 may be connected tothe second intermediate voltage node IVN2, the ground node GN, and asixth intermediate voltage node IVN6, and seventh capacitor divider 370may output an eighth voltage V8 at the sixth intermediate voltage nodeIVN6. Each of the first voltage node VN1, the third voltage node VN3,the first intermediate voltage node IVN3, the fourth intermediatevoltage node IVN4, the second voltage node VN2, the fifth intermediatevoltage node IVN5, the second intermediate voltage node IVN2, and thesixth intermediate voltage node IVN6 may be connected to respective oneof a plurality of load capacitors CL1, CL5, CL3, CL6, CL2, CL7, CL4 andCL8 coupled to the ground voltage, etc.

Each of the first through seventh capacitor dividers 310˜370 may performand/or operate one of a voltage drop operation and a voltage bootingoperation.

Therefore, when the DC-DC converter 210 provides a current to the firstvoltage node VN1 through the first power switch SW1, and the firstvoltage V1 is present at the first voltage node VN1, the first capacitordivider 310 provides the second voltage V2 to the second voltage nodeVN2 based on the first voltage VN1 as described with reference to FIGS.6B and 6C, the second capacitor divider 320, but the example embodimentsare not limited thereto. The second capacitor divider 320 provides thethird voltage V3 to the first intermediate voltage node IVN1 based onthe first voltage V1 and the second voltage V2, and the third capacitordivider 330 provides the fourth voltage V4 to the second intermediatevoltage node IVN2 based on the second voltage V2.

In addition, the fourth capacitor divider 340 provides the fifth voltageV5 to the third intermediate voltage node IVN3 based on the firstvoltage V1 and the third voltage V3, and the fifth capacitor divider 350provides the sixth voltage V6 to the fourth intermediate voltage nodeIVN4 based on the third voltage V3 and the second voltage V2. The sixthcapacitor divider 360 provides the seventh voltage V7 to the fifthintermediate voltage node IVN5 based on the second voltage V2 and thefourth voltage V4, and the seventh capacitor divider 370 provides theeighth voltage V8 to the sixth intermediate voltage node IVN6 based onthe fourth voltage V4.

Therefore, the voltage dividing capacitor circuit 300 c may generate andoutput a plurality of voltages corresponding to V1, (7/8)*V4, (6/8)*V1,(5/8)*V1, (4/8)*V1, (3/8)*V1, (2/8)*V1 and (1/8)*V1 to the first voltagenode VN1, the third voltage node VN3, the first intermediate voltagenode IVN3, the fourth intermediate voltage node IVN4, the second voltagenode VN2, the fifth intermediate voltage node IVN5, the secondintermediate voltage node IVN2 and the sixth intermediate voltage nodeIVN6, respectively, but the example embodiments are not limited thereto.The plurality of voltages corresponding to V1, (7/8)*V4, (6/8)*V1,(5/8)*V1, (4/8)*V1, (3/8)*V1, (2/8)*V1 and (1/8)*V1 have differentvoltage levels.

FIG. 11 is a circuit diagram illustrating an example of the voltagedividing capacitor circuit in the SIMO converter of FIG. 10 according tosome example embodiments.

Referring to FIG. 11 , the voltage dividing circuit 300 c may includethe first through seventh capacitor dividers 310-370, but is not limitedthereto.

The first capacitor divider 310 may include a plurality of transistors311, 312, 313 and 314, etc., connected in series between the firstvoltage node VN1 and the ground node GN, and a flying capacitor CFconnected between a node N11 and a node N12. According to some exampleembodiments, the flying capacitor CF may be connected in parallel to oneor more transistors, e.g., transistors 312 and/or 313, etc., but theexample embodiments are not limited thereto.

The transistor 311 is connected between the first voltage node VN1 andthe node N11, the transistor 312 is connected between the node N11 andthe second voltage node VN2, the transistor 313 is connected between thesecond voltage node VN2 and the node N12, and the transistor 314 isconnected between the second voltage node VN2 and the ground node GN,but the example embodiments are not limited thereto.

Each gate of the plurality of transistors 311 and 313 receives a firstphase control signal Φ1, and each gate of the plurality of transistors312 and 314 receives a first inversion phase control signal Φ1B whichhas a phase difference of 180 degrees with respect to the first phasecontrol signal Φ1, but the example embodiments are not limited thereto.When the transistors 311 and 313 are turned on, and the transistors a312and 314 are turned off, the first capacitor divider 310 stores, in theflying capacitor CF, a voltage corresponding to a difference between thefirst voltage V1 and the second voltage V2. When the transistors 311 and313 are turned off, and the transistors 312 and 314 are turned, thevoltage stored in the flying capacitor CF is provided to the secondvoltage node VN2 and stored in the second load capacitor CL2.

The second capacitor divider 320 may include a plurality of transistors321, 322, 323 and 324, etc., connected in series between the firstvoltage node VN1 and the second voltage node VN2, and a flying capacitorCF connected between a node N21 and a node N22, but the exampleembodiments are not limited thereto. Each gate of the transistors 321and 323 receives a second phase control signal Φ2, and each gate of thetransistors 322 and 324 receives a second inversion phase control signalΦ2B which has a phase difference of 180 degrees with respect to thesecond phase control signal Φ2, but is not limited thereto.

The third capacitor divider 330 may include a plurality of transistors331, 332, 333 and 334 connected in series between the second voltagenode VN2 and the ground node GN, and a flying capacitor CF connectedbetween a node N31 and a node N32. Each gate of the transistors 331 and333 receives a third phase control signal Φ3, and each gate of thetransistors 332 and 334 receives a third inversion phase control signalΦ3B which has a phase difference of 180 degrees with respect to thethird phase control signal Φ3, but is not limited thereto.

The fourth capacitor divider 340 may include a plurality of transistors341, 342, 343 and 344 connected in series between the first voltage nodeVN1 and the first intermediate voltage node IVN1, and a flying capacitorCF connected between a node N41 and a node N42. Each gate of thetransistors 341 and 343 receives a fourth phase control signal 14, andeach gate of the transistors 342 and 344 receives a fourth inversionphase control signal 14B which has a phase difference of 180 degreeswith respect to the fourth phase control signal 14, but is not limitedthereto. A node between the transistors 342 and 343 may be the thirdintermediate voltage node IVN3.

The fifth capacitor divider 350 may include a plurality of transistors351, 352, 353 and 354 connected in series between the first intermediatevoltage node IVN1 and the second voltage node VN2, and a flyingcapacitor CF connected between a node N51 and a node N52. Each gate ofthe transistors 351 and 353 receives a fifth phase control signal 15,and each gate of the transistors 352 and 354 receives a fifth inversionphase control signal 15B which has a phase difference of 180 degreeswith respect to the fifth phase control signal 15, but is not limitedthereto. A node between the transistors 352 and 353 may be the fourthintermediate voltage node IVN4.

The sixth capacitor divider 360 may include a plurality of transistors361, 362, 363 and 364 connected in series between the second voltagenode VN2 and the second intermediate voltage node IVN2, and a flyingcapacitor CF connected between a node N61 and a node N62. Each gate ofthe transistors 361 and 363 receives a sixth phase control signal Φ6,and each gate of the transistors 362 and 364 receives a sixth inversionphase control signal Φ6B which has a phase difference of 180 degreeswith respect to the sixth phase control signal Φ6, but is not limitedthereto. A node between the transistors 362 and 363 may be the fifthintermediate voltage node IVN5.

The seventh capacitor divider 370 may include a plurality of transistors371, 372, 373 and 374 connected in series between the secondintermediate voltage node IVN2 and the ground node GN, and a flyingcapacitor CF connected between a node N71 and a node N72. Each gate ofthe transistors 371 and 373 receives a seventh phase control signal Φ7,and each gate of the transistors 372 and 374 receives a seventhinversion phase control signal Φ7B which has a phase difference of 180degrees with respect to the seventh phase control signal Φ7, but is notlimited thereto. A node between the transistors 372 and 373 may be thesixth intermediate voltage node IVN6.

Operation of each of the second through fourth capacitor dividers320˜370 in a first state and a second state of a corresponding phasecontrol signal may be similar to the operations discussed in connectionwith FIGS. 6B and 6C, but the example embodiments are not limitedthereto.

FIG. 12 is a circuit diagram illustrating an example of the voltagedividing capacitor circuit in the SIMO converter of FIG. 10 according tosome example embodiments.

A voltage dividing circuit 300 cc in FIG. 12 differs from the voltagedividing circuit 300 c in FIG. 11 in that the voltage dividing circuit300 cc further include an eighth capacitor divider 380, but the exampleembodiments are not limited thereto.

Referring to FIG. 12 , the eighth capacitor divider 380 may be connectedbetween the first voltage node VN1 and the first intermediate voltagenode IVN1 in parallel with the fourth capacitor divider 340, but is notlimited thereto.

The eighth capacitor divider 380 may include a plurality of transistors381, 382, 383 and 384 connected in series between the first voltage nodeVN1 and the first intermediate voltage node IVN1, and a flying capacitorCF connected between a node N81 and a node N82. Each gate of thetransistors 381 and 383 receives the fourth inversion phase controlsignal Φ4B, and each gate of the transistors 382 and 384 receives thefourth phase control signal Φ4.

As described with reference to FIGS. 8B and 8C, the fourth capacitordivider 340 and the eighth capacitor divider 380 may operatecomplementarily in response to the fourth phase control signal Φ4 andthe fourth inversion phase control signal Φ4B, and may provideadditional current to the third intermediate voltage node IVN3 when acurrent provided to the load from the third intermediate voltage nodeIVN3 increases. At least one additional capacitor divider operatingcomplementarily may be connected to a load which consumes too muchcurrent and/or more current than desired, and the additional capacitordivider may supply additional current to the desired node rapidly.

FIG. 13 is a block diagram illustrating an example of a supply modulatoraccording to some example embodiments.

In FIG. 13 , a first power amplifier 90 a and a second power amplifier90 b are illustrated together for the sake of brevity and convenience ofexplanation, but the example embodiments are not limited thereto.

Referring to FIG. 13 , a supply modulator 100 b may include a maincontroller 110, a discrete level (DL) controller 120 a, a switchcontroller 130 a, a first switch array 140 a, a second switch array 140b, a third switch S31, a fourth switch S32 and/or a SIMO converter 200d, etc., but is not limited thereto.

The main controller 110 may receive the tracking mode signal TMS, theaverage power signal ART_REF, and the ET reference signal ET_REF from amodem, such as the modem 40 in FIG. 1 , and the main controller 110 maydetermine a tracking mode of the supply modulator 100 d based on thetracking mode signal TMS, but is not limited thereto. Additionally, themain controller 110 may generate a plurality of reference voltagesVREF1˜VREFn based on the ET reference signal ET_REF while in the ETmode, and may provide the plurality of reference voltages VREF1˜VREFn tothe SIMO converter 200 b. The main controller 110 may control thediscrete level controller 120 a, the switch controller 130 a and/or theSIMO converter 200 d, etc., but the example embodiments are not limitedthereto.

The SIMO converter 200 d may generate a plurality of voltages V1˜Vnbased on the battery voltage VBAT under the control of (and/or based onsignals received from) the main controller 110, and may provide theplurality of voltages V1˜Vn to the first switch array 140 a and/or thesecond switch array 140 b, etc. The SIMO converter 200 d may generate aplurality of APT voltages, such as first APT voltage APT_V1 and a secondAPT voltage APT_V2, based on the average power signal ART_REF while inthe APT mode, and the SIMO converter 200 d may provide the first APTvoltage APT_V1 to the first power amplifier 90 a through the thirdswitch S32 or may provide the second APT voltage APT_V2 to the secondpower amplifier 90 b through the fourth switch S33.

The SIMO converter 200 d may generate the plurality of voltages V1˜Vnhaving different voltage levels based on the plurality of referencevoltages VREF1˜VREFn and the battery voltage VBAT in the ET mode, andthe SIMO converter 200 d may output the plurality of voltages V1˜Vn tothe first switch array 140 a and the second switch array 140 b.

The first switch array 140 a may include a plurality of switches S1a˜Sna corresponding to the plurality of voltages V1˜Vn having differentvoltage levels. The second switch array 140 b may include a plurality ofswitches S2 a˜Snb corresponding to the plurality of voltages V1˜Vnhaving different voltage levels. The opening and closing operations ofthe plurality of switches S1 a˜Sna may be controlled by a switch controlsignal SWC1 provided from the switch controller 130 a. The opening andclosing operations of the plurality of switches 52 a˜Snb may becontrolled by a switch control signal SWC2 provided from the switchcontroller 130 a.

The switch controller 130 a may control on/off of the third switch S31and the fourth switch S32 using switch control signals SWC3 and SWC4under the control of (and/or based on signals received from) the maincontroller 110 while in the APT mode.

When the SIMO converter 200 d operates in an APT-APT mode, the switchcontroller 130 a may turn off the switches S1 a˜Sna and the switches 52a˜Snb, and may turn on the third switch S31 and the fourth switch S32.When the SIMO converter 200 d operates in an ET-ET mode, the switchcontroller 130 a may turn on one of the switches S1 a˜Sna and one of theswitches 52 a˜Snb, and may turn off the third switch S31 and the fourthswitch S32.

The discrete level controller 120 a may generate a first level controlsignal ENV_LV1 including envelope level information based on a firstenvelope signal ENV1 from the modem 40, and the discrete levelcontroller 120 a may generate a second level control signal ENV_LV2including envelope level information based on a second envelope signalENV2 from the modem 40. The discrete level controller 120 may providethe first level control signal ENV_LV1 and/or the second level controlsignal ENV_LV2 to the switch controller 130 a, but is not limitedthereto.

In the ET mode, the first switch array 140 a may select a first voltageamong the plurality of voltages V1˜Vn, and may provide the selectedfirst voltage to the first power amplifier 90 a as a first supplyvoltage VCC1. In the ET mode, the second switch array 140 b may select asecond voltage among the plurality of voltages V1˜Vn and may provide theselected second voltage to the second power amplifier 90 b as a secondsupply voltage VCC2. In addition, in the APT mode, the switch controller130 may control at least one of the plurality of switches S1˜Sn suchthat a voltage having a nearest level (e.g., closest voltage level,etc.) with a desired and/or required level and/or a greater level thanthe desired and/or required level among the plurality of voltages V1˜Vnis selected.

The first power amplifier 90 a may amplify a first RF input signalRF_IN1 based on the first supply voltage VCC1 or the first APT voltageAPT_V1 to generate a first RF output signal RF_OUT1. The second poweramplifier 90 b may amplify a second RF input signal RF_IN2 based on thesecond supply voltage VCC2 or the second APT voltage APT_V2 to generatea second RF output signal RF_OUT2.

The SIMO converter 200 d may operate in one of APT-APT mode, ET-APT modeand ET-ET mode, and may provide the plurality of voltages V1˜Vn to thefirst switch array 140 a and the second switch array 140 b, but theexample embodiments are not limited thereto.

FIG. 14 is a block diagram illustrating an example of the SIMO converterin the supply modulator in FIG. 13 according to some exampleembodiments.

In FIG. 14 , the first switch array 140 a, the second switch array 140b, the first power amplifier 90 a and the second power amplifier 90 bare illustrated together for the sake of brevity and convenience ofexplanation, but the example embodiments are not limited thereto.

Referring to FIG. 14 , a SIMO converter 200 d may include a DC-DCconverter 210, a voltage dividing capacitor circuit 300 d, a comparatorblock 220 d, PSCSG 230 d, and/or a PCSG 235 d, etc., but the exampleembodiments are not limited thereto.

The comparator block 220 d may include a plurality of comparators 221,222, 223 and 224 that compare each of a plurality of voltages V1, V2, V3and V4 with one of a plurality of reference voltages VREF1, VREF2, VREF3and VREF4, respectively, to generate and output a plurality ofcomparison signals CS21, CS22, CS23 and CS24 based on the results of thecomparisons.

The PSCSG 230 d may generate a first set of switch control signal SCScbased on a first comparison signal CS21, a second comparison signalCS22, and/or the tracking mode signal TYMS, and the PSCSG 230 d mayprovide the first set of switch control signal SCSc to the DC-DCconverter 210 d.

The PCSG 235 d may generate a phase control signal PCSa based on theplurality of comparison signals CS21, CS22, CS23 and CS24, and mayprovide the phase control signal PCSa to the voltage dividing capacitorcircuit 300 d. According to some example embodiments, the configurationof the voltage dividing capacitor circuit 300 d of FIG. 14 may be thesame as the configuration of the voltage dividing capacitor circuit 300a in FIG. 4 , but the example embodiments are not limited thereto.

The DC-DC converter 210 d may include the inductor 211, first througheighth power switches SW1, SW2, SW3, SW4, SW5, SW6, SW7 and SW8, and/orload capacitors CL1, CL12, CL2 and CL22, etc., but is not limitedthereto.

The inductor 211 may be connected between a first switching node SN1 anda second switching node SN2. The first power switch SW1 may be connectedbetween the first switching node SN1 and the first voltage node VN1, andthe first power switch SW1 may have a gate to receive a first switchcontrol signal SCS31. The second power switch SW2 may be connectedbetween the first switching node SN1 and the second voltage node VN2,and the second power switch SW2 may have a gate to receive a secondswitch control signal SCS32. The third power switch SW3 may be connectedbetween the first switching node SN1 and the ground node GN, and thethird power switch SW3 may have a gate to receive a third switch controlsignal SCS33. The fourth power switch SW4 may be connected between thesecond switching node SN2 and the battery voltage VBAT, and the fourthpower switch SW4 may have a gate to receive a fourth switch controlsignal SCS34.

The fifth power switch SW5 may be connected between the second switchingnode SN2 and the ground node GN, and the fifth power switch SW5 may havea gate to receive a fifth switch control signal SCS35. The sixth powerswitch SW6 may be connected between the first switching node SN1 and theload capacitor CL12, and the sixth power switch SW6 may have a gate toreceive a sixth switch control signal SCS36. The seventh power switchSW7 may be connected between the first switching node SN1 and the loadcapacitor CL22, and the seventh power switch SW7 may have a gate toreceive a seventh switch control signal SCS37. The eighth power switchSW8 may be connected between the battery voltage VBAT and the secondvoltage node VN2, and the eighth power switch SW8 may have a gate toreceive an eighth switch control signal SCS38.

The SIMO converter 200 d as shown in FIG. 14 may provide the first poweramplifier 140 a and the second power amplifier 140 b with a first supplyvoltage and a second supply voltage having different voltage levelsthrough the first switch array 140 a and the second switch array 140,and the SIMO converter 200 d may support APT mode and the ET mode, butis not limited thereto.

The SIMO converter 200 d may support at least one of an APT-APT mode,APT-ET mode, ET-APT mode, and/or ET-ET mode according to and/or based ona driving mode (e.g., operating mode, etc.) of the supply modulatorincluding the SIMO converter 200 d, but is not limited thereto.

When the SIMO converter 200 d operates in the ET-ET mode, the SIMOconverter 200 d may provide at least one of the voltages V1, V2, V3 andV4 generated in the voltage dividing capacitor circuit 300 d to thefirst power amplifier 140 a and the second power amplifier 140 b throughthe first switch array 140 a and the second switch array 140, but is notlimited thereto.

When the SIMO converter 200 d operates in the APT-ET mode, the DC-DCconverter 210 d provides a current to the voltage dividing capacitorcircuit 300 d via the first power switch SW1, and the voltage dividingcapacitor circuit 300 d generates the voltages V2, V3 and V4 based onthe voltage V1 to support the ET mode. In addition, the DC-DC converter210 d may generate an APT voltage using the sixth power switch SW6coupled to the load capacitor CL12 and the seventh power switch SW7coupled to the load capacitor CL22, and the DC-DC converter 210 d mayprovide the APT voltage to the second power amplifier 90 b using thesecond voltage node VN2 and the switch S32 as shown in FIG. 13 tosupport the APT mode, but is not limited thereto.

When the SIMO converter 200 d operates in the APT-APT mode, the DC-DCconverter 210 d maintains the voltages V1, V2, V3 and V4 in the voltagedividing capacitor circuit 300 d by using the eighth power switch SW8coupled to the battery voltage VBAT as a low-voltage drop out regulator,and the DC-DC converter 210 d may provide an APT voltage using the sixthpower switch SW6 coupled to the load capacitor CL12 and the seventhpower switch SW7 coupled to the load capacitor CL22, but is not limitedthereto.

FIG. 15 illustrates that the SIMO converter in FIG. 14 drives two poweramplifiers in ET-ET mode according to at least one example embodiment.

Referring to FIG. 15 , each of the plurality of power switches SW1, SW2,SW4 and SW5, etc., in the DC-DC converter 210 d is switched in responseto one of the switch control signals SCS31, SCS32, SCS34 and SCS35,respectively, and each of the power switches SW3, SW6, SW7 and SW8 inthe DC-DC converter 210 d is turned off in response to one of the switchcontrol signals SCS33, SCS36, SCS37 and SCS38, respectively.Accordingly, the DC-DC converter 210 d supplies current to the firstvoltage node VN1 and the second voltage node VN2, the voltage dividingcapacitor circuit 300 d generates the third voltage V3 and the fourthvoltage V4 based on the first voltage V1 and the second voltage V2, andthe voltage dividing capacitor circuit 300 d provides the first throughfourth voltages V1, V2, V3 and V4 to the first switch array 140 a andthe second switch array 140 b, but the example embodiments are notlimited thereto.

The first switch array 140 a may select one of the first through fourthvoltages V1, V2, V3 and V4 based on the first switch control signalSWC1. The first switch control signal SWC1 may be generated based on avoltage level of the first envelope signal ENV1. The first switch array140 a may provide the selected voltage to the first power amplifier 90a, and the second switch array 140 b may select one of the first throughfourth voltages V1, V2, V3 and V4 based on the second switch controlsignal SWC2 generated based on a voltage level of the second envelopesignal ENV2, and the second switch array 140 b may provide the selectedvoltage to the second power amplifier 90 b.

FIG. 16 illustrates that the SIMO converter in FIG. 14 drives two poweramplifiers in APT-APT mode according to at least one example embodiment.

Referring to FIG. 16 , each of the plurality of power switches SW3, SW4,SW5, SW6, SW7 and SW8, etc., in the DC-DC converter 210 d is switched inresponse to one of the switch control signals SCS33, SCS34, SCS35,SWC36, SWC37 and SCS38, respectively, and each of the power switches SW1and SW8 in the DC-DC converter 210 d is turned off in response to one ofthe switch control signals SCS31 and SCS32, respectively. Accordingly,the DC-DC converter 210 d provides the second voltage V2 to the voltagedividing capacitor circuit 300 d by using the eighth power switch SW8coupled to the battery voltage VBAT as a low-voltage drop out regulator,and the voltage dividing capacitor circuit 300 d generates a pluralityof voltages V1, V2, V3, and V4. The plurality of voltages V1, V2, V3,and V4 are prepared for a next ET mode. The DC-DC converter 210 d mayprovide an APT voltage using the sixth power switch SW6 coupled to theload capacitor CL12 and the seventh power switch SW7 coupled to the loadcapacitor CL22 as described with reference to FIG. 14 , but the exampleembodiments are not limited thereto.

FIG. 17A illustrates that the SIMO converter in FIG. 14 drives two poweramplifiers in ET-APT mode according to at least one example embodiment.

Referring to FIG. 17A, each of the plurality of power switches SW1, SW3,SW4, SW5, SW7 and SW8 in the DC-DC converter 210 d is switched inresponse to one of the plurality of switch control signals SCS31, SCS33,SCS34, SWC35, SWC37 and SCS38, respectively, and each of the powerswitches SW2 and SW6 in the DC-DC converter 210 d is turned off inresponse to one of the switch control signals SCS32 and SCS36,respectively. Accordingly, the DC-DC converter 210 d supplies current tothe first voltage node VN1 through the power switch SW1, and suppliescurrent to the second voltage node VN2 through the power switch SW8. Thevoltage dividing capacitor circuit 300 d generates the third voltage V3and the fourth voltage V4 based on the first voltage V1 and the secondvoltage V2. In addition, the DC-DC converter 210 d generates the APTvoltage using the power switch SW7 coupled to the load capacitor CL22and may provide the APT voltage through the first voltage node VN1.

FIG. 17B illustrates waveforms of the output voltage according to atracking mode in the SIMO converter in FIG. 14 according to at least oneexample embodiment.

FIG. 17B illustrates an output voltage waveform APT_V in the APT modeand an output voltage waveform ET_V in the ET mode, but is not limitedthereto.

Here, the APT is a technique for applying a modulation voltage to apower amplifier (e.g., the power amplifier 90 in FIG. 1 , etc.), themodulation voltage varying based on a peak level of an envelopeRF_OUT_ENV of a RF output signal RF_OUT for each desired and/orpredetermined transmission time interval (TTI). The ET is a techniquefor applying a modulation voltage to a power amplifier (e.g., the poweramplifier 90 in FIG. 1 , etc.), which instantaneously follows (and/orcorresponds to, etc.) a voltage level of the envelope RF_OUT_ENV of theRF output signal RF_OUT, but the example embodiments are not limitedthereto. The modulation voltage is limited to a plurality voltages (forexample, V11, V12, V13 and V14, etc.) having different voltage levelswhich the voltage dividing capacitor circuit 300 d is capable ofgenerating. In FIG. 17B, it is assumed that the output voltage waveformAPT_V has a level V′, but the example embodiments are not limitedthereto.

The envelope RF_OUT_ENV of the RF output signal RF_OUT may be generatedbased on amplitude of the RF output signal RF_OUT, but is not limitedthereto.

FIG. 18 is a circuit diagram illustrating a converter that employs twoDC-DC converters according to some example embodiments.

Referring to FIG. 18 , a converter 200 e may include a DC-DC converter210 d, a voltage dividing capacitor circuit 300 d, a comparator block220 d, a PSCSG 230 d, a PCSG 235 d, and/or a second DC-DC converter 210e, etc., but is not limited thereto.

The converter 200 e of FIG. 18 differs from the SIMO converter 200 b ofFIG. 9 in that the converter 200 e further includes the second DC-DCconverter 210 e, but the example embodiments are not limited thereto.

The second DC-DC converter 210 e may include an inductor 211 a and afirst through fifth power switches SW11, SW12, SW13, SW14 and SW15, etc.The inductor 211 a may be connected between a first switching node SN11and a second switching node SN12.

The first power switch SW11 may be connected between the first switchingnode SN11 and the first voltage node VN1, and the first power switchSW11 may have a gate to receive the first switch control signal SW31.The second power switch SW12 may be connected between the firstswitching node SN11 and the second voltage node VN2, and the secondpower switch SW12 may have a gate to receive the second switch controlsignal SW32. The third power switch SW13 may be connected between thefirst switching node SN11 and the ground node GN, and the third powerswitch SW13 may have a gate to receive the third switch control signalSW33. The fourth power switch SW14 may be connected between the secondswitching node SN12 and the battery voltage VBAT, and the fourth powerswitch SW14 may have a gate to receive the fourth switch control signalSCS34. The fifth power switch SW15 may be connected between the secondswitching node SN12 and the ground node GN, and the fifth power switchSW15 may have a gate to receive the fifth switch control signal SCS35.

The DC-DC converter 210 d and the second DC-DC converter 210 e may beconnected to the same nodes, and the DC-DC converter 210 d and thesecond DC-DC converter 210 e may share the voltage dividing capacitorcircuit 300 d and increase the processing capacity and/or efficiency ofthe circuit.

FIG. 19 is a circuit diagram illustrating a converter that employs twoDC-DC converters according to some example embodiments.

Referring to FIG. 19 , a converter 200 f may include a DC-DC converter210 d, a voltage dividing capacitor circuit 300 d, a comparator block220 d, a PSCSG 230 d, a PCSG 235 d, and/or a second DC-DC converter 210f, etc., but the example embodiments are not limited thereto.

The converter 200 f of FIG. 19 differs from the SIMO converter 200 b ofFIG. 9 in that the converter 200 e further includes the second DC-DCconverter 210 f, but the example embodiments are not limited thereto.

The second DC-DC converter 210 fe may include an inductor 211 a andfirst through fifth power switches SW21, SW22, SW23, SW24 and SW25, butis not limited thereto. The inductor 211 a may be connected between afirst switching node SN21 and a second switching node SN22.

The first power switch SW21 may be connected between the first switchingnode SN21 and the first intermediate voltage node IVN1, and the firstpower switch SW21 may have a gate to receive the first switch controlsignal SW31. The second power switch SW22 may be connected between thefirst switching node SN21 and the second intermediate voltage node IVN2,and the second power switch SW22 may have a gate to receive the secondswitch control signal SW32.

The third power switch SW23 may be connected between the first switchingnode SN21 and the ground node GN, and the third power switch SW23 mayhave a gate to receive the third switch control signal SW33. The fourthpower switch SW24 may be connected between the second switching nodeSN22 and the battery voltage VBAT, and the fourth power switch SW24 mayhave a gate to receive the fourth switch control signal SCS34. The fifthpower switch SW15 may be connected between the second switching nodeSN22 and the ground node GN, and the fifth power switch SW15 may have agate to receive the fifth switch control signal SCS35.

The DC-DC converter 210 d may supply current to the first voltage nodeVN1 and the second voltage node VN2 based on the battery voltage VBAT,and the second DC-DC 210 f may supply current to the first intermediatevoltage node IVN1 and the second intermediate voltage node IVN2 based onthe battery voltage VBAT. Therefore, the converter 200 f may providecurrent to the first voltage node VN1, the second voltage node VN2, thefirst intermediate voltage node IVN1, and/or the second intermediatevoltage node IVN2 without passing through the capacitor divider, andthereby may increase the efficiency of the circuit.

According to some example embodiments, the DC-DC converter 210 d and thesecond DC-DC converter 210 f may employ DC-DC converters with differentconfigurations, and are not limited thereto.

FIG. 20 is a circuit diagram illustrating an example of a voltagedividing capacitor circuit according to some example embodiments.

Referring to FIG. 20 , a voltage dividing capacitor circuit 300 e mayinclude first through fourth capacitor dividers 310 a, 320, 330 and 340a, but the example embodiments are not limited thereto.

The first capacitor divider 310 a may include a plurality of transistors311, 312, 313, 314, 315 and 316, etc., connected in series between thefirst voltage node VN1 and the ground node GN, and two flying capacitorCF may be connected between a node N11 and a node N13. A first loadcapacitor CL1 may be connected between the first voltage node VN1 andthe ground voltage.

The transistor 311 is connected between the first voltage node VN1 andthe node N11, the transistor 312 is connected between the node N11 andthe second voltage node VN2, the transistor 313 is connected between thesecond voltage node VN2 and the node N12, the transistor 314 isconnected between the node N12 and a third voltage node VN3, thetransistor 315 is connected between the third voltage node VN3 and anode N13, and the transistor 315 is connected between the node N13 andthe ground node GN.

Each gate of the transistors 311, 313 and 315 receives a first phasecontrol signal Φ1, and each gate of the transistors 312, 314 and 316receives a first inversion phase control signal Φ1B which has a phasedifference of 180 degrees with respect to the first phase control signalΦ1, but is not limited thereto. The first capacitor divider 310 a maygenerate the second voltage V2 and the third voltage V3 based on thefirst voltage V1 at the first voltage node VN1, and may provide thesecond voltage V2 and the third voltage V3 to the second voltage nodeVN2 and the third voltage node Vn3, respectively.

The configuration and operation of each of the second capacitor divider320 and the third capacitor divider 330 may be similar to the secondcapacitor divider 320 and the third capacitor divider 330 described inFIG. 7A, but are not limited thereto. A second load capacitor CL2 may beconnected between the second voltage node VN2 and the ground voltage. Athird load capacitor CL3 may be connected between the third voltage nodeVN3 and the ground voltage. A fourth load capacitor CL4 may be connectedbetween a first intermediate voltage node IVN1 and the ground voltage. Afifth load capacitor CL5 may be connected between a first intermediatevoltage node IVN1 and the ground voltage.

The fourth capacitor divider 340 a may include a plurality oftransistors 341 a, 342 a, 343 a and 344 a connected in series betweenthe third voltage node VN3 and the ground node GN, and a flyingcapacitor CF may be connected between a node N41 a and a node N42 a. Thetransistor 341 a is connected between the third voltage node VN3 and thenode N41 a, the transistor 342 a is connected between the node N41 a andthe third intermediate voltage node IVN3, the transistor 343 a isconnected between the third intermediate voltage node IVN3 and the nodeN42 a, and the transistor 344 a is connected between the node N42 a andthe ground node GN.

Each gate of the transistors 341 a and 343 a receives a fourth phasecontrol signal Φ4, and each gate of the transistors 342 a and 344 areceives a fourth inversion phase control signal Φ4B which has a phasedifference of 180 degrees with respect to the fourth phase controlsignal Φ4, but is not limited thereto. The fourth capacitor divider 340a may generate a sixth voltage V6 based on the third voltage V3 and mayprovide the sixth voltage V6 to the third intermediate voltage nodeIVN3.

FIG. 21 is a circuit diagram illustrating an example of a voltagedividing capacitor circuit according to some example embodiments.

Referring to FIG. 21 , a voltage dividing capacitor circuit 300 f mayinclude first through fifth capacitor dividers 310, 320, 330, 340 a and350 a, but is not limited thereto.

Configuration of each of the first through third capacitor dividers 310,320 and 330 of FIG. 21 may be substantially the same as configuration ofeach of the first through third capacitor dividers 310, 320 and 330 inFIG. 7A, and configuration of the fourth capacitor divider 340 a of FIG.21 may be substantially the same as configuration of the fourthcapacitor divider 340 a in FIG. 20 , but the example embodiments are notlimited thereto.

The fifth capacitor divider 350 a may include a plurality of transistors351 a, 352 a, 353 a and 354 a connected in series between the secondvoltage node VN2 and the ground node GN, and a flying capacitor CF maybe connected between a node N51 a and a node N52 a.

The transistor 351 a is connected between the second voltage node VN3and the node N51 a, the transistor 352 a is connected between the nodeN51 a and the third voltage node VN3, the transistor 353 a is connectedbetween the third voltage node VN3 and the node N52 a, and thetransistor 354 a is connected between the node N52 a and the ground nodeGN.

Each gate of the transistors 351 a and 353 a receives a fifth phasecontrol signal Φ5, and each gate of the transistors 352 a and 354 areceives a fifth inversion phase control signal Φ5B which has a phasedifference of 180 degrees with respect to the fifth phase control signalΦ5, but is not limited thereto. The fifth capacitor divider 350 a maygenerate a third voltage V3 based on the second voltage V2, and mayprovide the third voltage V3 to the third voltage node VN3.

FIG. 22 is a circuit diagram illustrating an example of a voltagedividing capacitor circuit according to some example embodiments.

A voltage dividing capacitor circuit 300 g of FIG. 22 has aconfiguration in which the second capacitor divider 320 is omitted fromthe voltage dividing capacitor circuit 300 a in FIG. 7A. The voltagedividing capacitor circuit 300 g may include the first capacitor divider310 and the third capacitor divider 330 in FIG. 7A. Therefore, thevoltage dividing capacitor circuit 300 g may have a reduced number ofload capacitors and/or switches.

In FIG. 22 , the first voltage node VN1 may be referred to as a firstnode, the ground node may be referred to as a second node and the secondvoltage node may be referred to as a third node.

FIG. 23 is a circuit diagram illustrating an example of a voltagedividing capacitor circuit according to some example embodiments.

A voltage dividing capacitor circuit 300 h of FIG. 23 has aconfiguration in which the third capacitor divider 330 is omitted fromthe voltage dividing capacitor circuit 300 a in FIG. 7A. The voltagedividing capacitor circuit 300 h may include the first capacitor divider310 and the second capacitor divider 320 in FIG. 7A, but is not limitedthereto. Therefore, the voltage dividing capacitor circuit 300 h mayhave a reduced number of load capacitors and/or switches.

In FIG. 23 , the first voltage node VN1 may be referred to as a secondnode, the ground node may be referred to as a first node, and the secondvoltage node may be referred to as a third node.

Referring to FIGS. 22 and 23 , at least one capacitor divider associatedwith a voltage that is not used, may be omitted from a plurality ofcapacitor dividers included in the voltage dividing capacitor circuit,and the number of load capacitors and/or switches included in thevoltage dividing capacitor circuit may be reduced.

The voltage dividing capacitor circuit, the SIMO converter and thesupply modulator according to some example embodiments may be employedin various communication devices, may reduce power consumption of thecommunication device, and may enhance performance of the communicationdevice.

The foregoing is illustrative of some example embodiments and is not tobe construed as limiting thereof. Although a few some exampleembodiments have been described, those skilled in the art will readilyappreciate that many modifications are possible in the some exampleembodiments without materially departing from the novel teachings andadvantages of the inventive concept. Accordingly, all such modificationsare intended to be included within the scope of the inventive concept asdefined in the claims.

What is claimed is:
 1. A voltage dividing capacitor circuit comprising:a first capacitor voltage divider connected to a second voltage node,the first capacitor voltage divider including a first flying capacitorand a plurality of first switches, the second voltage node coupled to asecond load capacitor, the plurality of first switches connected inseries between a first voltage node and a ground node, the first voltagenode coupled to a first load capacitor, and the ground node coupled to aground voltage; and a second capacitor voltage divider connected betweenthe first voltage node and the second voltage node, the second capacitorvoltage divider including a second flying capacitor and a plurality ofsecond switches, and the plurality of second switches connected inseries between the first voltage node and the second voltage node. 2.The voltage dividing capacitor circuit of claim 1, further comprising: athird capacitor voltage divider connected between the second voltagenode and the ground node; and wherein the first capacitor voltagedivider is configured to, receive a first voltage at the first voltagenode, generate a second voltage corresponding to one half of the firstvoltage, and output the second voltage to the second voltage node. 3.The voltage dividing capacitor circuit of claim 2, wherein: the secondcapacitor voltage divider is configured to, generate a third voltagebased on the first voltage and the second voltage, and output the thirdvoltage to a first intermediate voltage node, the first intermediatevoltage node coupled between the plurality of second switches; the thirdcapacitor voltage divider includes a third flying capacitor and aplurality of third switches, the plurality of third switches connectedin series between the second voltage node and the ground node, and thethird capacitor voltage divider is configured to, generate a fourthvoltage based on the second voltage and the ground voltage, and outputthe fourth voltage to a second intermediate voltage node, the secondintermediate voltage node coupled between the plurality of thirdswitches; the third voltage corresponds to one half of a sum of thefirst voltage and the second voltage; and the fourth voltage correspondsto one half of the second voltage.
 4. The voltage dividing capacitorcircuit of claim 1, wherein the first capacitor voltage divider isconfigured to: receive a second voltage at the second voltage node;generate a first voltage corresponding to double the second voltage; andoutput the first voltage to the first voltage node.
 5. The voltagedividing capacitor circuit of claim 1, further comprising: a thirdcapacitor voltage divider connected between the second voltage node anda third voltage node, the third voltage node coupled to the firstcapacitor voltage divider and the third voltage node; and a fourthcapacitor voltage divider connected between the third voltage node andthe ground node, and wherein the first capacitor voltage divider isconfigured to, receive a first voltage at the first voltage node,generate a second voltage and a third voltage based on the receivedfirst voltage, and output the second voltage and the third voltage tothe second voltage node and the third voltage node, respectively.
 6. Thevoltage dividing capacitor circuit of claim 5, wherein: the secondcapacitor voltage divider is configured to generate a fourth voltagebased on the first voltage and the second voltage, and output the fourthvoltage to a first intermediate voltage node, the first intermediatevoltage node coupled between the plurality of second switches; the thirdcapacitor voltage divider includes a third flying capacitor and aplurality of third switches, the plurality of third switches connectedin series between the second voltage node and the ground node, and thethird capacitor voltage divider is configured to generate a fifthvoltage based on the second voltage and the third voltage, and outputthe fifth voltage to a second intermediate voltage node, the secondintermediate voltage node coupled between the plurality of thirdswitches; the fourth capacitor voltage divider includes a fourth flyingcapacitor and a plurality of fourth switches, the plurality of fourthswitches connected in series between the third voltage node and theground node, and the fourth capacitor voltage divider is configured togenerate a sixth voltage based on the third voltage and the groundvoltage, and output the sixth voltage to a third intermediate voltagenode coupled between the plurality of fourth switches; the fourthvoltage corresponds to one half of a sum of the first voltage and thesecond voltage; the fifth voltage corresponds to one half of a sum ofthe second voltage and the third voltage; and the sixth voltagecorresponds to one half of the third voltage.
 7. A voltage dividingcapacitor circuit comprising: a first capacitor voltage dividerincluding a first flying capacitor and a plurality of first switches,the plurality of first switches connected in series between a firstvoltage node and a third voltage node, the first voltage node coupled toa first load capacitor, the third voltage node coupled to a third loadcapacitor, and the first capacitor voltage divider connected to a secondvoltage node coupled to a second load capacitor; a second capacitorvoltage divider connected between the first voltage node and the secondvoltage node; a third capacitor voltage divider connected between thesecond voltage node and the third voltage node; a fourth capacitorvoltage divider connected between the third voltage node and a groundnode coupled to a ground voltage; and a fifth capacitor voltage dividerconnected between the second voltage node and the ground node.
 8. Thevoltage dividing capacitor circuit of claim 7, wherein the firstcapacitor voltage divider is configured to: receive a first voltage atthe first voltage node; generate a second voltage corresponding to onehalf of the first voltage; and output the second voltage to the secondvoltage node.
 9. The voltage dividing capacitor circuit of claim 8,wherein: the second capacitor voltage divider includes a second flyingcapacitor and a plurality of second switches, the plurality of secondswitches connected in series between the first voltage node and thesecond voltage node, and the second capacitor voltage divider isconfigured to generate a fourth voltage based on the first voltage andthe second voltage, and output the fourth voltage to a firstintermediate voltage node coupled between the plurality of secondswitches; the fifth capacitor voltage divider includes a fifth flyingcapacitor and a plurality of fifth switches, the plurality of fifthswitches connected in series between the second voltage node and theground node, and the fifth capacitor voltage divider is configured togenerate a third voltage based on the second voltage and the groundvoltage, and output the third voltage to the third voltage node; thethird capacitor voltage divider includes a third flying capacitor and aplurality of third switches, the plurality of third switches connectedin series between the second voltage node and the third voltage node,and the third capacitor voltage divider is configured to generate afifth voltage based on the second voltage and the third voltage, andoutput the fifth voltage to a second intermediate voltage node coupledbetween the plurality of third switches; the fourth capacitor voltagedivider includes a fourth flying capacitor and a plurality of fourthswitches, the plurality of fourth switches connected in series betweenthe third voltage node and the ground node, and the fourth capacitorvoltage divider is configured to generate a sixth voltage based on thethird voltage and the ground voltage, and output the sixth voltage to athird intermediate voltage node coupled between the plurality of fourthswitches; the fourth voltage corresponds to one half of a sum of thefirst voltage and the second voltage; the third voltage corresponds toone half of the second voltage; the fifth voltage corresponds to onehalf of a sum of the second voltage and the third voltage; and the sixthvoltage corresponds to one half of the third voltage.
 10. A supplymodulator comprising: a DC-DC converter including an inductor connectedto a battery voltage; first through third power switches connectedbetween the inductor and one of a first voltage node, a second voltagenode and a ground node, respectively, the ground node coupled to aground voltage; a first load capacitor, the first load capacitorconnected between the first voltage node and the ground node; a secondload capacitor, the second load capacitor connected between the secondvoltage node and the ground node; and a voltage dividing capacitorcircuit including at least two capacitor voltage dividers, the at leasttwo capacitor voltage dividers connected to the first voltage node, thesecond voltage node and the ground node, wherein the DC-DC converter isconfigured to generate a current based on an energy stored in theinductor, and output the current to at least one of the first voltagenode and the second voltage node based on a first set of switch controlsignals, and the voltage dividing capacitor circuit is configured togenerate a plurality of voltages having different levels based on thecurrent, and output the plurality of voltages to the first voltage node,the second voltage node and a first and second intermediate voltagenodes, the first intermediate voltage node connected between the firstvoltage node and the second voltage node, and the second intermediatevoltage node connected between the second voltage node and the groundnode.
 11. The supply modulator of claim 10, further comprising: acomparator block including a plurality of comparators, the plurality ofcomparators each configured to, compare one of the plurality of voltagesand one of a plurality of reference voltages, and generate a pluralityof comparison signals based on results of the comparisons; a powerswitch control signal generator configured to generate a first set ofpower switch control signals based on a first comparison signal of theplurality of comparison signals, and a second comparison signal of theplurality of comparison signals, the first comparison signal associatedwith the first voltage node, the second comparison signal associatedwith the second voltage node, the power switch control signal generatorconfigured to provide the first set of power switch control signals tothe DC-DC converter; and a phase control signal generator configured togenerate a set of phase control signals based on the plurality ofcomparison signals, the phase control signal generator configured toprovide the phase control signal to the voltage dividing capacitorcircuit.
 12. The supply modulator of claim 10, wherein the voltagedividing capacitor circuit includes: a first capacitor voltage dividerconnected between the first voltage node and the ground node; a secondcapacitor voltage divider connected between a first terminal of thefirst load capacitor and a first terminal of the second load capacitor;and a third capacitor voltage divider connected between the secondvoltage node and the ground node, wherein the first capacitor voltagedivider includes a plurality of first switches connected in seriesbetween the first voltage node and the ground node, and a first flyingcapacitor connected between the plurality of first switches, the secondcapacitor voltage divider includes a plurality of second switchesconnected in series between the first voltage node and the secondvoltage node, and a second flying capacitor connected between theplurality of second switches, and the third capacitor voltage dividerincludes a plurality of third switches connected in series between thesecond voltage node and the ground node, and a third flying capacitorconnected between the plurality of third switches.
 13. The supplymodulator of claim 12, wherein in response to a first voltage isprovided to the first voltage node, the first voltage generated based onthe current: the first capacitor voltage divider is configured togenerate a second voltage corresponding to one half of the firstvoltage, and output the second voltage to the second voltage node; thesecond capacitor voltage divider is configured to generate a thirdvoltage based on the first voltage and the second voltage, and outputthe third voltage to a first intermediate voltage node connected betweenthe plurality of second switches; the third capacitor voltage divider isconfigured to generate a fourth voltage based on the second voltage andthe ground voltage, and output the fourth voltage to a secondintermediate voltage node connected between the plurality of thirdswitches; and the third voltage corresponds to one half of a sum of thefirst voltage and the second voltage and the fourth voltage correspondsto one half of the second voltage.
 14. The supply modulator of claim 10,wherein the voltage dividing capacitor circuit includes: a firstcapacitor voltage divider connected between the first voltage node andthe ground node; a second capacitor voltage divider connected betweenthe first voltage node and the second voltage node; a third capacitorvoltage divider connected between the second voltage node and a thirdvoltage node, the third voltage node coupled to the first capacitorvoltage divider and a third load capacitor; and a fourth capacitorvoltage divider connected between the third voltage node and the groundnode, wherein the first capacitor voltage divider includes a pluralityof first switches connected in series between the first voltage node andthe ground node, and a first flying capacitor connected between theplurality of first switches, the second capacitor voltage dividerincludes a plurality of second switches connected in series between thefirst voltage node and the second voltage node, and a second flyingcapacitor connected between the plurality of second switches, the thirdcapacitor voltage divider includes a plurality of third switchesconnected in series between the second voltage node and the thirdvoltage node, and a third flying capacitor connected between theplurality of third switches, and the fourth capacitor voltage dividerincludes a plurality of fourth switches connected in series between thethird voltage node and the ground node, and a fourth flying capacitorconnected between the plurality of fourth switches.
 15. The supplymodulator of claim 14, wherein in response to a first voltage beingprovided to the first voltage node, the first voltage generated based onthe current: the first capacitor voltage divider is configured togenerate a second voltage and a third voltage based on the firstvoltage, and output the second voltage and the third voltage to thesecond voltage node and the third voltage node respectively; the secondcapacitor voltage divider is configured to generate a fourth voltagebased on the first voltage and the second voltage, and output the fourthvoltage at a first intermediate voltage node connected between theplurality of second switches; the third capacitor voltage divider isconfigured to generate a fifth voltage based on the second voltage andthe third voltage, and output the fifth voltage to a second intermediatevoltage node connected between the plurality of third switches; and thefourth capacitor voltage divider is configured to generate a sixthvoltage based on the third voltage and the ground voltage, and outputthe sixth voltage to a third intermediate voltage node connected betweenthe plurality of fourth switches.
 16. The supply modulator of claim 10,wherein the voltage dividing capacitor circuit includes: a firstcapacitor voltage divider connected to the first voltage node, thesecond voltage node, and a third voltage node coupled to a third loadcapacitor; a second capacitor voltage divider connected between thefirst voltage node and the second voltage node; a third capacitorvoltage divider connected between the second voltage node and the thirdvoltage node; a fourth capacitor voltage divider connected between thethird voltage node and the ground node; and a fifth capacitor voltagedivider connected between the second voltage node and the ground node,wherein the first capacitor voltage divider includes a plurality offirst switches connected in series between the first voltage node andthe third voltage node, and a first flying capacitor connected betweenthe plurality of first switches, the second capacitor voltage dividerincludes a plurality of second switches connected in series between thefirst voltage node and the second voltage node, and a second flyingcapacitor connected between the plurality of second switches, the thirdcapacitor voltage divider includes a plurality of third switchesconnected in series between the second voltage node and the thirdvoltage node, and a third flying capacitor connected between theplurality of third switches, the fourth capacitor voltage dividerincludes a plurality of fourth switches connected in series between thethird voltage node and the ground node, and a fourth flying capacitorconnected between the plurality of fourth switches, and the fifthcapacitor voltage divider includes a plurality of fifth switchesconnected in series between the second voltage node and the ground node,and a fifth flying capacitor connected between the plurality of fifthswitches.
 17. The supply modulator of claim 16, wherein in response to afirst voltage being provided to the first voltage node, the firstvoltage generated based on the current: the first capacitor voltagedivider is configured to generate a second voltage based on the firstvoltage, and output second voltage to the second voltage node; thesecond capacitor voltage divider is configured to generate a fourthvoltage based on the first voltage and the second voltage, and outputthe fourth voltage to a first intermediate voltage node connectedbetween the second switches; the third capacitor voltage divider isconfigured to generate a fifth voltage based on the second voltage and athird voltage, and output the fifth voltage to a second intermediatevoltage node connected between the third switches; and the fourthcapacitor voltage divider is configured to generate a sixth voltagebased on the third voltage and the ground voltage, and output the sixthvoltage to a third intermediate voltage node connected between thefourth switches.